The two girls are so alike that strangersfind________difficult to tell one from the other.

Why do you look so worried? —Fred left the company half an hour agoHis work _______ unfinished since

up _______ youfell down, and I’m sure you’ll succeed in time

You look so tired today.What happened，Jack—I didn’t go to bed ________ 12 o’clock last night because there was too much homework.

Well, let’s play computer games.—That ________ good.