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We’ve seen that sentences have an internal structure. They consist of constituents which
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themselves may consist of smaller constituents. So far, we’ve looked at it in a kind of
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theoretical way. But now, we can take that and put it into practice, and the question
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is going to be then, if you have a sequence of words, if you have a string of words, how
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can you determine what the constituents are that make up that string? What is the evidence
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for a certain sequence of words being a constituent or not being a constituent? That is to say,
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are there diagnostics for constituent structure that can be applied?
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The main two diagnostics that can be used to work out what the constituent structure
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of a sentence or a phrase is, are, on the one hand, whether that sequence that you’re
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looking at can be replaced by a single word. So that’s one family of tests for constituency:
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replacement or substitution tests… whether you can replace the sequence that you’re
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concerned with by a single word.
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And the other main class of tests for constituency is movement or displacement, that is, can
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that same sequence of words that you’re looking at and trying to work out whether
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it’s a constituent, can that sequence of words be moved within the sentence, can it
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be displaced and occur somewhere else, while the meaning of the whole sentence is more
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or less preserved? That may not make a lot of sense at the moment, but you’ll see some
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examples. So those are the two main types of test that can be used for constituency.
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When we’ve looked at those, we’ll look at some others as well.
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Now we’re looking at how we can diagnose constituency, and in particular starting with
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the test that we can call substitution or replacement.
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Noun phrases are one kind of phrase, a phrase that’s built round a noun, evidently. And
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that’s the general pattern, that inside each phrase there’s one distinguished word
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that gives the phrase its category. So we have noun phrases which are built around nouns.
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We’ll see that you have adjective phrases built around adjectives, prepositional phrases
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built around prepositions. That distinguished word within a phrase is called the head of
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the phrase. Other terminology that gets used for this is to say that a word projects a
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phrase. So a noun projects a noun phrase; an adjective projects an adjective phrase.
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So a noun projects a noun phrase; the noun is head of that phrase.
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One reason for saying that the noun is the ‘distinguished’ word within the noun phrase
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is that it’s the word that is least likely to be omitted. So this is characteristic of
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heads of phrases. So there are lots of sizes of noun phrases. We can have, for example,
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uh, just the word ‘cats’, so we could say “Cats are lovely”. We can also say
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“Intelligent cats are lovely”; we can say “Cats with long tails are lovely”,
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or “Intelligent cats with long tails are lovely”. In all of these, of course, we’ve
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got the word ‘cats’. If we omit that, we’d wind up things… wind up with things
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like “intelligent with long tails are lovely” or “with long tails are lovely”, and those
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are ungrammatical. So in this case we see that it’s the head of the phrase that has
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to be there, that can’t be omitted. And that’s typical, perhaps not entirely universal,
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but a typical property of the head of the phrase.
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A second fact about the head of the phrase is that it shares grammatical properties with
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the phrase. We’ve already seen that it shares the category, so a noun is the head of a noun
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phrase, so that grammatical category of noun is shared between head and phrase, but other
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grammatical properties may be projected from the head to the phrase. One property, for
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example, is plurality. For example, you could take in English a phrase like “the dog”.
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“The dog” is singular, and you can tell because if you add a verb you get singular
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agreement on the verb. So you’d say “The dog is waiting” and not “The dog are waiting”.
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Of course, you would say “The dogs are waiting”. So the noun phrase there is plural, and notice,
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because the head is plural. We could take another noun phrase like, uhm, “seven heads”.
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Right, so that’s plural — you’d say “seven heads are better than one”. Now,
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we can make a larger noun phrase; we’ve seen that you can have phrases inside phrases,
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so we could have a larger noun phrase where you’d put these together. So we’d get
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something like “the dog with seven heads”. Now notice what happens if you try to make
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a verb agree with that. You’ll get “the dog with seven heads was waiting”, not “the
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dog with seven heads were waiting”. So despite the fact that ‘heads’, which is plural,
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is close to the verb, it’s not what the verb is agreeing with. The verb is sensitive
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to the number that is determined by the head of the phrase and the head of the whole noun
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phrase “the dog with seven heads” is ‘dog’, which is singular. So the number of the head
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inside the phrase determines the number of the whole phrase.
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In English we can see this with plurality. There are other grammatical properties which
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can be determined by the head of the noun phrase. Uh, we don’t see in English, but
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in many languages nouns are divided into a number of classes which are sometimes called
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genders. In different languages the number of different genders, the number of these
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formal classes of nouns varies. Uhm, you may be familiar with French, which has two distinct
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genders, masculine and feminine, and all nouns fall into one or other of those classes. And
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again, just like plurality in English and, in fact, plurality in French, the gender of
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a noun phrase is determined by the gender of the head. And one way to see this is that
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other words also agree with it, so we saw that in English the verb agrees in number
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with the number of the noun phrase that’s the subject. In French we get also agreement
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in gender on adjectives. So you could have a sentence like, uhm, “La mère est morte.”
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So ‘mère’, mother, is feminine, it makes the whole noun phrase feminine, and the adjective
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‘morte’ has a ‘te’ sound at the end which is the feminine agreement. On the other
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hand, if you had a masculine word like, uhm, ‘Georges’, the man’s name ‘George’,
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that would be masculine, and if you wanted to say “George is dead”, you would get
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“Georges est mort”, without that ‘te’ sound at the end. So again, the… in this
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case the gender of the head determines the gender of the whole phrase. And again we can
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build up a larger phrase, so we could have “La mère de Georges” (the mother of Georges),
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and if we now see what gender we get on the adjective, we get “La mère de Georges est
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morte”, again with the feminine ending. So there again, although the word that’s
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closest to the adjective is masculine, the agreement that you get on the adjective is
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feminine, because the whole noun phrase (“the mother of Georges”), the agreement that
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you get on the adjective is feminine, because the whole noun phrase, ‘the mother of George’,
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the gender of that is determined by the noun ‘mother’. So there again we see a grammatical
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property of a head of a phrase projected to the whole phrase.
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There’s a classic example in the literature that relies on this property of heads. If
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you take the phrase “Visiting relatives can be boring”, it’s actually ambiguous,
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there’s two quite distinct meanings. So on the one hand it means something like “relatives
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who visit can be boring”, and on the other hand it means something quite different, that
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is going to see relatives yourself can be boring.
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So it has these two meanings. But notice it’s a property of the word ‘can’ that it actually
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doesn’t show agreement for singular or plural. So you say “the boy can” and “the boys
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can”. But if you take a verb that does show a difference, now we can see the ambiguity
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actually splitting up. So you’d say “Visiting relatives is boring” or “Visiting relatives
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are boring”. And those two sentences now, each one only has one of the meanings. And
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you’ve got that different agreement. And what’s happening there is that where you
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get “Visiting relatives are boring”, on that reading where it’s the relatives who
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are boring, ‘relatives’ is the head of the noun phrase “visiting relatives”.
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It’s plural, so the whole noun phrase is plural and you get plural agreement.
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But with the other meaning, where it means “to visit relatives is boring”, in that
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case the noun ’visiting’ is the head of the noun phrase, and that is singular, so
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you get singular agreement on the verb. So there you see a very minimal example which
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shows that the head of the noun phrase is determining the number on the noun, and in
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this case it goes with a very real difference in the meaning of the noun phrase as a whole.
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So that’s some properties of phrases and heads of phrases, and in particular of noun
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phrases, but now to get back to the question of the diagnostic for noun phrases, and in
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particular the diagnostic of substitution or replacement. A characteristic of noun phrases,
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then, is that they can be replaced by a single word which is called a ‘pronoun’. So that’s
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what pronouns do. Notice that although we call them pronouns, it’s actually a bad
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term, because a pronoun doesn’t replace a noun — it replaces a whole noun phrase.
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So, for example, if you take a sentence like “John saw the boy who fed the cats”. We
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could replace the whole sequence “the boy who fed the cats” with the pronoun ‘him’.
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So “John saw the boy who fed the cats. I saw him too.” And ‘him’ is referring
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to that whole sequence (“the boy who fed the cats”), so that tells us it’s a noun
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phrase.
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Notice that you could also say “John saw the boy who fed the cats. I saw the girl who
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fed them”, where now ‘them’ is replacing ‘the cats’. So that is also a constituent;
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it’s also a noun phrase. So, should we be worried that we have one diagnostic which
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says “the boy who fed the cats” is a noun phrase and another diagnostic that says “the
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cats” is a noun phrase? Well, obviously not, because we’ve seen that phrases can
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contain other phrases. Constituents contain constituents. And in particular we have recursive
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cases of this, that a noun phrase can contain another noun phrase. And this is just one
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example of that.
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We’ve looked a bit now at noun phrases, at phrases headed by nouns. Now we can look
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at another kind of phrase, a prepositional phrase. That is, a phrase headed by a preposition.
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Prepositions in English include words like ‘in’, ‘on’, ‘after’, and so on.
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It’s actually a bit unfortunate that we have this word preposition, because it includes
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within it the ordering the preposition has with respect to the phrase it combines with.
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So in English, prepositions precede the phrase they combine with, so we get “in London”,
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“from Japan”, “to Edinburgh”: preposition followed by a noun phrase.
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In other languages you have postpositions, that is, the equivalent kind of word, but
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that follows the phrase that it combines with.
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In Japanese, you’d find that the equivalent of a preposition occurs after the noun phrase
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it combines with. So in English we’d say “to Tokyo”; in Japanese you’d say “Tokyo
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e” or “Tokyo ni”, and the same with all of the equivalent words. By calling them
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prepositions versus postpositions, it makes it sound like it’s two different categories.
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What we’d really want to say is that there’s a single category which we could call adpositions.
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And that in English they go before the thing they combine with; in Japanese they go after.
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But preposition and postposition are very well-established terms, so we’ll stick to
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those for the moment.
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So in English, our adpositions are prepositions; they come before the thing that they combine
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with, which is typically a noun phrase, although we’ll see that there are examples of prepositions
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combining with other categories.
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Prepositions can express different kinds of concepts. Prepositions that relate to location,
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or locative prepositions, when those combine with phrases, the result can often be replaced
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by a locative expression like ‘there’ or ‘here’. So, I could say, for example,
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“I went to Philadelphia in 1985. I went there in 1985.” “I came to Edinburgh in
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2002. I came here in 2002.” So locative prepositional phrases can often be replaced
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with ‘here’ or ‘there’. Other prepositions can denote things to do with time, and these
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temporal phrases that result can also be replaced often with a temporal word like ‘then’.
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So, we could say “She lived in Philadelphia in 2008. She lived in Philadelphia then.”
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We could do both, so “She lived in Philadelphia in 2008. She lived there then.” We’ve
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replaced the two prepositional phrases with these two words: ‘there’ and ‘then’.
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Other prepositions denote other concepts than time or place. So, for example, there’s
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a preposition ‘for’. It has many uses, but you could say “I did this for my aunt”.
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There’s no single word that can replace ‘for my aunt’. We still think it’s a
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prepositional phrase, but it doesn’t have a corresponding single word, like ‘there’
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or ‘then’. We’ll see later on, though, that there are other diagnostics that we can
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use to show that it is indeed a phrase.
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We’ve seen noun phrases headed by nouns. We’ve seen prepositional phrases headed
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by prepositions. Another type of phrase is an adjective phrase. An adjective could be
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a word like ‘ill’ or ‘loud’, and these could be expanded to make larger phrases.
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So we could say, for example, “Mary is extremely ill” or “That noise is too loud to be
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tolerable”. “Extremely ill” is an adjective phrase” — “too loud to be tolerable”…
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also an adjective phrase.
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For some speakers, these adjective phrases can be replaced by the form ‘so’. For
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such speakers, you could say “Marion seems extremely ill, and Bill is so too”, where
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‘so’ picks up “extremely ill”. But not every speaker uses ‘so’ in this way.
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Not every speaker accepts that. I myself find don’t find it very natural. For speakers
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who do have that use of ‘so’, it’s a good diagnostic for an adjective phrase. At
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least, even for such speakers, though, there is a caveat here. Adjective phrases appear
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in two main types of position. You can use adjective phrases attributively or predicatively.
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What that means is, to use something predicatively, to use an adjective phrase predicatively is
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to use it in a phrase like “Marion is ill” or “The mantlepiece is dusty”. To use
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it attributively is to use it within the noun phrase, so “a very ill woman” or “a
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dusty mantlepiece”.
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And even speakers who can use ‘so’ to replace adjective phrases, can only do so
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when those adjective phrases appear in the predicative position, so you’ll have speakers
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who can say “She is very tall, and my brother is so too” but the same speakers don’t
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accept, for example, “I saw a very tall man, and she saw a so woman”. So that use
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of ‘so’ is restricted to adjective phrases in predicative position for the speakers who
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can use it.
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And the final type of phrase that we’ll consider now is a phrase headed by a verb,
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a verb phrase. Verb phrases can occur in various positions. An example would be “To insult
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your mother is disgraceful”. “Insult your mother” there is a verb phrase. Or “Jenny
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will attend the conference”. “Attend the conference” is a verb phrase. Or “Laura
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painted a portrait of the dog”. “Painted a portrait of the dog” is a verb phrase.
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The substitution that you can do for verb phrases is actually not with a single word.
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Verb phrases can often be replaced with the form ‘do so’. So for example you can say
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“To insult your mother is disgraceful. To do so is disgraceful.” So “insult your
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mother” there we saw is a verb phrase, and indeed we can replace it with ‘do so’.
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Or “Jennifer will attend the conference. I will do so too. I will attend the conference
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too.” So we can see that “attend the conference” is also a verb phrase.
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Or “Laura painted a portrait of the dog. Her sister did so too. Her sister painted
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a portrait of the dog too.” So “painted a portrait of the dog”: also a verb phrase
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— as you can see, a complex verb phrase which contains a noun phrase inside it. So
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‘do so’ is the form that can substitute for an entire verb phrase.