1 . Those responsible NGOs ________ (take) various measures to deal with the increasingly serious pollution. (所给词的适当形式填空)

2 . Ladies and gentlemen, please fasten your seat belts. The plane _______(take) off. (所给词的适当形式填空)

3 . We can say “it’s ________(rain)”. （所给词的适当形式填空）

4 . Betty ________(leave) for Guangzhou by plane at 3:00 this afternoon. （所给词的适当形式填空）

5 . I can guess you were in a hurry, for you __________ (wear) your sweater inside out. (所给词的适当形式填空)

6 . Please be quiet. The child ____________(concentrate) on his experiment. (所给词的适当形式填空)

7 . My aunt ________(return) from the UK tonight. I'll go to the airport to pick her up. (所给词的适当形式填空）

8 . The prices of houses ________(rise) because the demand for houses is becoming greater and greater. (所给词的适当形式填空）

9 . Our principal ________ (plan) for the coming holiday now, and he is visiting the Terracotta Army with his family. (所给词的适当形式填空）

10 . The mid-term exam ________ (come), and everyone is trying hard to study.（所给词的适当形式填空）