Justin     a book about his adventures in Tibet．I hope he can find a good publisher when it is finished．

Allen has decided that he will be an engineer by the time he ________ twenty.

— How long have you known John? — Since he ______ to our class.

 __________ to sun, rain and wind for a long time, the stone split（裂开）.

Since I won the big prize, my telephone hasn't stopped ringing. People ______ to ask how I am going to spend the money.