我国城市燃气管道按燃气设计压力分为()级
A.5
B.6
C.7
D.8
参考答案:C
There was going to ___ a struggle between her two friends. She doesn't know __ to deal with it. [ ]
A. be, how
B. has, what
C. be, what
D. have, how
作为政策影响的重点是()。
A.附加结果
B.净结果
C.正结果
D.负结果