阅读理解，选择合适的答案。

    Winter is very cold. Sometimes it snows in winter. We can play with the snow. We can make snowmen.

We usually wear warm clothes. My favourite season is winter, because my birthday is in December.

1. Winter is ______．

A. cold    

B. warm    

C. hot

2. Sometimes it ______ in winter.

A. rains    

B. snows    

C. snow

3. What can we do in winter?  

A. We can swim.

B. We can make snowmen.

C. We can plant trees and flowers.

4. We usually wear _______ in winter.

A. shirts    

B. shorts    

C. warm clothes

5. Which one below is right?

A. I don't like winter.

B. I like to swim in winter.

C. My birthday is in December.

M型超声心动图二尖瓣曲线图，箭头所示两点称为（）

A.E点和A点

B.D点和C点

C.A点和G点

D.上点和下点

E.前点和后点