锥体束受累各种深反射受何影响（）
A.减低
B.增高
C.不变
D.可以增高或降低
E.以上均不正确
参考答案：B
The ____ expression on his face suggested that he ____ understand what I said.
A．puzzling, should not
B．puzzled, did not
C．puzzle, was not
D．puzzled, not
层数超过( )层的高层建筑，其机械加压送风的防排烟系统应分段设计。
A．10
B．20
C．32
D．36
