根据句意及首字母提示补全单词。

1. He often goes swimming during summer v_______.

2. My favorite pet is a cat. Because it's funny and l_______.

3. Chatting on the Internet can bring us happiness and f_______.

4. —Who taught you to swim?

    —N_______. I taught myself.

5. —What's your hobby?

    —I like c_______ coins very much.

设计有围护结构的深基础架空层层高在( )及以上的部位应计算全面积。

A．2.1m

B．2.2m

C．2.3m

D．2.5m