根据句意及单词首写字母完成句子。

1. The ice is very thick. Let's go s         .

2. The students are r         money for the poor.

3. Jack has been in the club s       two years ago.

4. Several s          have been skating for 2 hours.

5. D     the second World War, many European Jews came to Shanghai.

厥证最突出最常见的病因是（）

A.失血过多

B.嗜酒肥甘

C.情志刺激

D.正气虚弱

E.空腹劳累