胶带跑偏的基本规律()。
A.偏大不偏小
B.偏高不偏低
C.偏紧不偏松
D.偏后不偏前
参考答案:A, B, C, D
与结核分枝杆菌致病性有关的物质是 ()
A.索状因子
B.磷脂
C.蜡质D
D.硫酸脑苷脂
E.分枝菌酸
Now the air in our city is ______ than it used to be. Something must be done to stop it.
A.good
B.bad
C.worse
D.better