You would be well advised to do so.
そうしたほうがいいですよ
You would like to see it, perhaps?
それを見たいの，ひょっとして
You [Anyone] would think [would have thought] (that) ....
普通は…だと考えますよね（◆はずれた予想を述べる）
You wouldn't dare!
君にはとてもやれまい
You yourself are responsible for the lost book.
その本の紛失の責任はあなた自身にあります
You yourself told me so.＝You told me so yourself.
あなた自身が私にそう言ったのだ
You'd be wise to phone ahead.
事前に電話を入れる方が賢明だろう
You'd better leave now, or else you'll miss your plane.
もう出発しなさい，でないと飛行機に乗り遅れますよ
You'd better pull up a bit.
少し休んだほうがよい
You'd ought to think twice before you talk about murder like that.
そんなに簡単に人殺しの話なんかするもんじゃない．
