标准麻花钻的顶角2φ为()±2°。
A、110°
B、118°
C、122°
D、128°
参考答案:B
_________the freezing wind ,they_________ the injured man in time. They felt sorry for that.
A.Had not been for ;could reach
B.If there was not; might have reached
C.But for; might reach
D.If there hadn’t been ; could have reached
My mother said I ________ hard-working.[ ]
A. am
B. were
C. was
D. 'm