上缸猫爪结构的优点是承力面与汽缸的水平中分面在一个平面内，能较好地保持汽缸与转子的中心一致。
参考答案：对
输血可传播疾病，最常见的是（）
输血可传播疾病，最常见的是：
A.艾滋病
B.肝炎
C.肾炎
D.血液疾病
E.感染
在下列各句的每个空格内填上一个适当的完整的单词，该词的首字母已给。
小题1: The man had nothing to eat for two days, so he is very h _________.
小题2: The music is too boring, so all of us d _________ it.
小题3: I don’t want to go to that cinema. It has the w_________ service in town.
小题4: The farmer went on working ，a _________ it rained heavily。
小题5: You bought lots of things for us, but nothing for y__________.
