检修风缸时，其腐蚀深度超过（）时须更换。
A.30％
B.40％
C.50％
D.60％
参考答案：C
--- Do you know what Tom does all day ?
---- I know he spends at least as much time watching TV as he ____________his lessons.
A．is doing
B．does
C．spends to do
D．does doing
临床上，脾不统血可以导致出血，其出血特点是（）
A.血色紫黯
B.血色鲜红
C.血色淡红
D.血液黏稠
E.夹有血块
