Which sign means "Save Water"? [ ]
A. B. C. D.
答案：D
China succeeded ______ sending up its first man-made satellite (卫星) ______1970. [ ]
A. on, in
B. on, on
C. in, in
D. at, in
环境保护要素包括以下（）。
A．维修区域环境
B．职工宿舍
C．钣金区域环境
D．漆工区域环境
E．其他区域环境
B. 
C. 
D. 
B. C. D.