在浇注系统中主要起档渣作用的是（）
A.直浇道
B.横浇道
C.内浇道
参考答案：B
The chairman asked me to ________the report, because he didn't want to speak for too long at this meeting.
A．cut out
B． cut in
C．cut off
D．cut down
救生艇是一种非常有效的脱险工具。（）
