根据句意和首字母提示写出单词。

1. Tom is very helpful. He often gives his s_______ to the old people on the bus.

2. The flu (流感) is a big p_______ in the world now. We must be careful.

3. We all like our English teacher because she is always w______ to help us.

4. — What do you want to be in the f_______?

    — I want to be a singer because I like traveling.

5. The a_______ by the 15-year-old girl are very popular among the young people now.

下列选项中，债券的发行价格不包括( )。

A．超价发行

B．低价发行

C．高价发行

D．等价发行