装饰抹灰水刷石阴阳角垂直度允许偏差是多少检查方法是什么
参考答案：装饰抹灰水刷石阴阳角垂直度允许偏差不应大于4mm。其检查方法用2m托线板检查。
用所给动词的适当形式填空。
1. I'm calling to tell you that I ___________ (not be) able to go to the gym with you tonight.
2. The teacher told us that light ___________ (travel) much faster than sound.
3. I ___________ (think) they were having a meeting at that time．
4. I will go with you if she ___________ (go).
5. If it ___________ (rain) tomorrow, I won't go to the museum.
脑底动脉环在脑循环中起着非常重要的作用，能沟通脑前、后、左、右的血液供应，下列哪条动脉不参与脑底动脉环的组成（）
A.大脑前动脉
B.前交通动脉
C.颈内动脉
D.大脑后动脉
E.椎动脉
