气门座的工作面出现()时,不一定需要镶座铰削修磨。
A.密封环带磨损变宽超过3mm
B.斑点
C.烧蚀出现凹陷
D.出现积炭
参考答案:D
A.(A) I know many business people at the Beachside Hotel.
B.(B) The Beachside is the only favorite hotel for many business people.
C.(C) Many business people like to hold conferences in the Beachside Hotel.
D.(D) Many business people provide the best conference facilities for the Beachside.
不属癌性溃疡的X线征象()
A.龛影不规则
B.龛影呈半月形
C.龛影位于胃轮廓之外
D.周围有半月形透亮带
E.环堤附近黏膜皱襞呈杵状