单项选择题
Lifeboat launching is operated at intervals of （）months.
A.one
B.two
C.three
D.four
点击查看答案&解析
相关考题
-
单项选择题
Fire drill is carried out once a （）.
A.year
B.day
C.week
D.month -
单项选择题
Any emergency pump situated （）machinery space should also be started.
A.outside
B.under
C.beside
D.besides -
单项选择题
On hearing the fire signal, the crew should proceed immediately to （）their assigned duties.
A. carry on
B. put out
C. carry out
D. take off
