1 . The disappearance of dinosaurs is not necessarily caused by astronomical incidents, but alternative explanations are hard ________.

A．found

B．to be found

C．finding

D．to find

3 . Rewards can stimulate people _____ (do) good deeds. (所给词的适当形式填空)

4 . I think part of the problem is how we educate people _______(work)in this field. (所给词的适当形式填空)

5 . Funds are available _________(assist) teachers who want to attend the conference. (所给词的适当形式填空)

6 . Compared with adults, children are more eager (渴现的) to ________(探索世界) around them. (根据汉语提示完成句子)

7 . 我们应该尽我们最大的努力过一个低碳的生活。（汉译英）

8 . Please remind her_______ (return) early. (所给词的适当形式填空)

9 . The deal is estimated ________ (be) worth around $1.5 million. （所给词的适当形式填空）

10 . ________ (catch) the early flight, we ordered a taxi in advance and got up very early. (所给词的适当形式填空)