Depending on how long you have known the person, and whether or not the two of you have exchanged phone numbers, added each other on social media, or have mutual friends, figure out which method works best for you.
這要取決於你認識對方多久,你有沒有他的手機號碼、有沒有在社群網站上加他好友、有沒有共同好友之類的,好好地思考這些問題並找出最適合自己的方法。