掘进机履带应松紧适宜,松弛度为()mm。
A.20—40
B.30—50
C.40—60
参考答案:B
___ the left, he suddenly found the tailor’s shop he was looking for.
A.T be turning
B.Turning to
C.To turn
D.Turned to
某学龄儿童采用0.05%NaF漱口水预防龋齿,其正确的使用方法应为()
A.每月含漱1次,含漱1分钟
B.每周含漱1次,含漱1分钟
C.每天含漱1次,含漱1分钟
D.隔周含漱1次,含漱1分钟
E.隔天含漱1次,含漱1分钟