Many people can’t learn any lessons from the mistakesthey’ve made _____ they get hurt somehow.

The American Civil War lasted four years the North won in the end.[ ]

Have you got any books on English grammar I want toborrow______.Yes, here you are. But you must return it by Friday.

Are you angry? — Yes. He should at least answer when ____.

–When did the concert_____?—Oh, two days ago.