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【单选题】
第一心音产生的主要原因是A.
房室瓣开放
B.
房室瓣关闭
C.
动脉瓣开放
D.
动脉瓣关闭
E.
心室快速充盈
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【简答题】Young people can have problems with their minds. Some students become worried because they have to study very hard and they have too much homework to do every day. Others have trouble getting on well ...
【多选题】湿地必须满足的条件的是:
A.
地表长期或季节性的积水或过湿状态
B.
生长着湿生、沼生、浅水生的植物还有动物及适应这种环境的微生物类群
C.
发育水生或半水生的土壤
D.
具有潮湿的气候
【简答题】阅读理解。 Young people can have problems with their minds. Some students become worried because they have to study very hard. Others have trouble getting on well with people like their parents and classma...
【简答题】Young people can have problems with their minds. Some students become worried because they have to study very hard. Others have trouble getting on well with people lik e parents and classmates. Liu We...
【简答题】D Young people can have problems with their minds. Some students become worried because they have to study very hard. Others have trouble getting on well with people like their parents and classmates....
【单选题】听力原文：Bill Gates didn't finish his undergraduate study, therefore some young students fantasize that they could also become millionaires if they drop out. (24)
A.
Bill Gates is rich because he didn't finish his undergraduate study.
B.
Bill Gates tells us that in order to become rich, one must drop out.
C.
Some students believe that they don't need education, but can still be rich.
D.
Some students have become millionaires after they drop out.
【简答题】Young people can have problems with their minds. Some students become worried because they have to study very hard. Others have trouble getting on well with people like their parents and classmates. L...
【简答题】Young people can have problems with their minds. Some students become worried because they have to study very hard. Others have trouble getting on well with people like their parents and classmates. L...
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