溃疡深大，呈菜花状，基底及边缘硬有浸润，疼痛不明显的是
A．结核性溃疡B．创伤性溃疡C．癌性溃疡D．腺周口疮E．梅毒下疳
参考答案：C
– Mike, I won the first prize in the speech contest last week.
-- ___!
A．Congratulations
B．Enjoy yourself
C．Good luck
D．No way.
过滤罐为什么要进行反冲？
