问题
单项选择题
隔膜计量泵的（）结构由泵头、膜片、进出口单向阀组、柱塞、填料等构成。
A、泵壳
B、泵体
C、泵头
D、泵介质腔
答案
参考答案：D
搜题请搜索小程序“爱下问搜题”
隔膜计量泵的（）结构由泵头、膜片、进出口单向阀组、柱塞、填料等构成。
A、泵壳
B、泵体
C、泵头
D、泵介质腔
参考答案：D
Passage One
According to the man, why shouldn’t people be worried about climbing onto an elephant
A．Because elephants are mild animals.
B．Because elephants are trained to carry goods.
C．Because people have designed safe ways for the climbing.
D．Because people will be aided by professional assistants.