1 . I find it no use ________ about it now. I really regret ________ the exam.

A．to argue; to fail

B．arguing; to fail

C．to argue; failing

D．arguing; failing

2 . The research mainly deals with the difficulty the students have ________ their attention on their study all the time.

A．to focus

B．to be focused

C．focusing

D．focused

3 . 我们应该鼓励学生表达自己的想法，而不是只听老师讲解。(as opposed to)
We should encourage students to express their own ideas, _________________

4 . Experts suggest smiling at yourself in the mirror to ________. And if we are feeling ________, there is ________.
专家建议对着镜子微笑来让自己更快乐、更坚强。而且如果我们感到沮丧或孤独，没有什么比看到好朋友的笑脸更好的了。

5 . 奥运会上也有一些志愿者，他们为奥运会提供服务，比如负责运动员的食宿。（汉译英）

6 . 他去农村的目的是促进那里的教育。(objective，promote)（汉译英）

7 . 钢是由铁加碳制造而成的。
Steel is produced by__________ carbon.

8 . 为了支持新冠病例的接收工作，建筑工人一接到建设方舱医院的安排任务就立即行动起来，并尽力在指定期限之前就完成了任务。
To back up the reception of COVID-19 cases, the construction workers________ ________ ________upon________ ________ the task of building the mobile cabin hospital(方舱医院), and endeavored to finish it________to the deadline.

9 . 作为一个人口大国，粮食短缺仍是我国突出问题也不足为奇，需要付出更多努力来提高产量。（dedicate）（汉译英）

10 . After he had turned off the TV set, he began to go over his lessons. （用动词的-ing形式改写）
________________