裂隙
参考答案：
是坚硬岩石形成时或形成之后由于各种内外应力的作用，使岩体遭受破坏而形成的空隙。
-Can he get the first prize for running?
-Impossible now. He _______ so, but he has just hurt his leg.
A．would expect to do
B．was expected to do
C．has expected doing
D．is expected doing
慢性支气管炎急性发作的主要原因是：（）
A.劳累
B.呼吸系统感染
C.过敏性反应
D.吸烟
E.药物
