拉阻风门拉钮或多次踩加速踏板,勉强能起动发动机,加速时化油器有回火现象,但很快就熄火,则可诊断是()。
A、混合气过浓
B、不来油或来油不畅
C、点火时间过早
参考答案:B
24小时咯血量超过多少为大咯血()。
A.50ml
B.100ml
C.200ml
D.300ml
E.500ml
Thank you for all your hard work last week. I don’t think we ______ it without you.[ ]
A. could have managed
B. can manage
C. can have managed
D. could manage