1．(湖南卷)If nothing ____________(do), the oceans will turn into fish deserts.
答案：is done
2．Before you leave the classroom，the door and windows should ____________(close) in case of rain.
答案：be closed
3．Every possible means ____________(try) by the company to improve its production.
答案：has been tried
4．The car which is under repair____________(belong) to Mr Green.
答案：belongs
5．There’s a crowd of people over there. Go and see what ____________(sell)．
答案：is being sold
6．Over the past few years, a large number of houses ____________(build) for the lowincome families.
答案：have been built
7．The woman was walking about outside the operation room, because her son ____________(operate) on.
答案：was being operated
8．He said the work ____________(finish) in half an hour with the help of classmates.
答案：would be finished
9．The palace caught fire three times in the last century, and little of the original building ____________(remain) now.
答案：remains
10．In the near future, more advances in the robot technology ____________(make) by scientists.
答案：will be made
