管式泵由于检泵作业油管上卸次数多,所以油管螺纹易磨损。
参考答案:对
通常所指的头颈部肿瘤除外的是()。
A.甲状腺癌
B.鼻咽癌
C.脑胶质瘤
D.口腔癌
E.外耳道鳞癌
Now,many Chinese are buying their own house. Over the past years, the price of real estates has doubled and redoubled, but people still wait in queues for their chance to buy.