影响底板突水的主要因素有（）。
A.水源条件
B.地质构造
C.隔水层
D.矿山压力
E.底板岩性
参考答案：A, B, C, D
照样子写句子。
例：松鼠和小熊是好朋友。
（1）__________和__________是__________。
（2）__________和__________是__________。
根据句意和所给首字母补全单词
1.His father is an e_____,and he designs ( 设计) a lot of bridges.
2.The Chinese g_____didn't want a foreigner for a Chinese railroad.
3.It was difficult to build the railroad because there were a lot of bridges and t_____.
4.Mr. Smith is the h_____of Mrs. Smith.
5.Yang Liwei is a great a_____in China.
