在下列各句的空白处填入一个适当的词，使句子意思完整，语法正确。

1. My daughter bought a new _________ of shoes for me.

2. I haven't _________ your letter yet. When did you send it?

3. I don't like having classes on Saturday. Me __________.

4. The traffic is busy at that time. You'd better be careful to _________ the street.

5. It is better to keep your voice down in _________ places.

关于接触性皮炎正确的是

A．具有自限性

B．愈后不留色素沉着

C．无再发

D．均在较高浓度时才致病

E．无水疱形成