Tian'anmen Square _________ famous. [ ]
A. is
B. was
C. were
答案:A
属于重介质选煤的优点的是()。
A、设备磨损低
B、分选效率和分选精度高
C、工艺简单
D、加工费用低
寸口部位所指的三部九候包括
A.寸关尺
B.天人地
C.浮中沉
D.上中下
E.人迎,气口,趺阳