He has read many books on history, so it’s _________ for him to answer these questions.

How many English words had you learned _____ the end of last term? — Around 2000, but I’ve forgotten most of them. [ ]

It was some time ________ we realized that we lost the chance forever.

Have you found your English book?—No, I haven’t found ________, but I borrowed ________ from Jack this afternoon.

You look pale. What’s _______ with you? —I have _______ headache.