马尾包括哪些脊神经根()?
A. T12以下
B. L1以下
C. L2以下
D. L3以下
E. L4以下
连续切削的精加工及半精加工刀具常用()制造。
A. 陶瓷材料
B. 热压氮化硅
C. 立方氮化硼
D. 金刚石
The police are thetraffic accident that happened yesterday.
A. looking down upon
B. looking forward to
C. looking into
D. looking after
--________of his parentsliked pop music.-- So they did. It isnoisy.
All
B. None
C. Both
D. Neither