旋塞阀的塞子顶端露出的方头上均刻有沟槽，该沟槽系指()(A)增大

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问题单项选择题

旋塞阀的塞子顶端露出的方头上均刻有沟槽，该沟槽系指()

(A)增大摩擦力;

(B)开启和关闭位置;

(C)机械生产阀时无意带的;

(D)漏雨水用

答案

参考答案：B

选择题

　　　　　　in 1914 　　　　　　the First World War broke out?

A．Was that, that　　　

B．Was that, when

C．Was it. that

D．Was it, when

选择题

Many high school students are _____ to go to college, but _____about failing the entrance examinations.

A. eager… generous B. eager…keen C. anxious…eager eager… anxious