脊柱活动度最大的椎体是（）。
A.颈椎和腰椎
B.颈椎和胸椎
C.腰椎和骶椎
D.胸椎和腰椎
E.胸椎
参考答案：A
— Did you hear about Zhang Lili who saved the kids from being run over by a school bus?
— Yes. What do you think most people _____ if they were in a similar situation?
A．will do
B．will have done
C．would do
D．would have done
机油泵内限压阀的作用是什么？
