精密铝合金零件镀覆前常采用()进行脱脂处理。
A、酒精
B、汽油
C、四氯乙烯
D、甲苯
参考答案:C
I don't think it was an accident at all. Your brother did it _____. [ ]
A. for purpose
B. on purpose
C. in order
D. by chance
肾气不固的主要表现是
A.久病咳喘,呼多吸少
B.男子阳痿,女子经闭
C.五更泄泻,完谷不化
D.男子滑精早泄,女子带下清稀