止回阀中的压力能使阀芯在阀座上就位。
参考答案:对
Only after his friend came _______.
A.did the computer repaired
B.was repaired the computer
C.was the computer repaired
D.the computer was repaired
彭女士,30岁,有产后大出血,休克史,继之出现闭经,生殖器萎缩,脱发,乏力,此闭经属于
A.丘脑性闭经B.垂体性闭经C.卵巢性闭经D.子宫性闭经E. * * 横膈