对井下断裂构造的观测主要有那些方面？
参考答案：
对断裂构造，应观测其断距，产状、断层带厚度，断裂带充填物成分、胶结程度及出水情况。
When I try to find _______ that prevents so many people from taking part in the program,it seems to me that there are two main causes.
A．why it does
B．what it does
C．what it is
D．why it is
防御措施介绍
