可摘局部义齿卡环设计时,应该避免使用过多的卡环,卡环数量以多少为宜
A.超过5个
B.不超过4个
C.不超过3个
D.不能超过6个
E.不能超过7个
参考答案:B
跳汰机正常生产时的表观现象有哪些?
—Could you tell us what has happened to Mary?
—She ________ to the picnic next weekend if her business trip to Hawaii had not been cancelled. [ ]
A. would not go
B. would not have gone
C. shall not go
D. shouldn't have gone