undetectable

US

UK

B1 中級
adj.形容詞不能探察的
An undetectable tracking device was installed in the secret agent's watch

影片字幕

我們能走多遠?人類的極限。 (How Far Can We Go? Limits of Humanity.)

07:45我們能走多遠?人類的極限。 (How Far Can We Go? Limits of Humanity.)