透平低、中速暖机时要保持机体导淋、抽汽导淋畅通。
参考答案:对
男性,12岁,平素无症状,心电图如图3-5-3所示,应考虑为()。
A.右心室肥大
B.双侧心室肥大
C.右位心
D.左心房心律,侧壁心肌梗死
E.右心房下部心律
—There used to be lots of fish in the lake.
—Yes, but there are very __________ now. [ ]
A. few
B. fewer
C. little
D. less