煤层顶板，是指位于煤层上面的岩层，叫煤层顶板，煤层顶板还分成：伪顶、直接顶、基本顶。
参考答案：对
My new classmate told us about his trip to _____ Great Wall. He said it was _____ exciting experience for him. [ ]
A. the; an
B. /; the
C. the; /
D. /; a
装饰工程中属于装饰抹灰的有（）。
A.水刷石
B.水磨石
C.斩假石
D.大理石
