弯制卡环的要点是什么?

- Grandpa has changed a lot.

- So he has. He spends more time than he used to ______ games

with the children.

A．play

B．playing

C．played

D．plays

She's jogging around the park every morning in a(n) _______ to have a good figure.[ ]

A. contribution        

B. effort              

C. honour            

D. purpose

图示为铸铁给水管道（）胶圈柔性接口。

A.楔形

B.角唇形

C.螺栓压盖形

D.中缺形

15℃以下为超深低温，用于长时间停止循环时器官保护，低温过程常需进行下述哪些监测（）

A.动脉压

B.ECG

C.多部位测温

D.血气

E.尿量

在软硬交错地层如何优选牙轮钻头？