《煤矿安全质量标准化标准》规定,采煤工作面采用液压支架支护时,支架要排成直线,其偏差不得超过()。
A.±50m
B.±100m
C.±150m
D.±200m
参考答案:A
It's fun to look at the pictures when I finish ______. [ ]
A. draw
B. drawing
C. to draw
D. draws