上颌切牙有()
A.唇舌面的外形高点在中1/3
B.中切牙切缘与近中切角近似直角
C.上颌侧切牙近中切角似锐角
D.上颌侧切牙舌窝较浅
E.较常发生变异
参考答案:B
Bob would have helped us yesterday, but he _____. [ ]
A. was busy
B. is busy
C. had been busy
D. will be busy
各基层单位每月召开一次HSE例会,各班组()召开一次HSE例会。
A.每月
B.每周
C.每日
D.每班