成形磨削时,要求砂轮外形保持的时间长些,应选用粒度号较小的砂轮。( )
参考答案:错
She asked me ___________ the news to him.
A.not tell
B.to not tell
C.not telling
D.not to tell
下列选项中,那几项是岩心录井所必须的设备或工具()
A、石蜡
B、岩心盒
C、标签
D、棉纱