根据句子的意思和所提供的汉语，补充句子，使句子通顺完整。

1.他日夜工作以还清债务。

He worked                             to pay off the debt.

2.我急切盼望你的回信。

I’ m                              your reply.

3.他考试作弊，怎么没受到惩罚呢？

How did he                          cheating in the exams?

4.Don’t bother to look for my umbrella; it will ________ ________some day. (出现)

5.The race was so close that everyone was ________ ________ ________ at the finish. (屏住呼吸)

6.He couldn’t ________ ________ his foolish mistake. (作出解释)

7.经济危机首先在美国爆发。

The economic crisis ________ ________ first in the United States.

8.I must ________ ________ this morning and do the cleaning. (安下心来)