皮皮学，免费搜题
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【单选题】
心室舒张充盈期防止血液逆流的装置是A.
主动脉瓣和二尖瓣
B.
肺动脉和三尖瓣
C.
主动脉瓣和三尖瓣
D.
主动脉瓣和肺动脉瓣
E.
二尖瓣和三尖瓣
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皮皮学刷刷变学霸
举一反三
【单选题】—How do you know that she likes singing? —I often hear her _____ after class. [ ]
A.
to sing
B.
sing
C.
sings
【单选题】—Miss wang once art at Bardon School for ten years and now is a singer. —No wonder I often hear her sing in the garden.
A.
had taught
B.
taught
C.
is teaching
D.
has been teaching
【单选题】— How do you know that she likes singing? — I often hear her ____ after class. [ ]
A.
to sing
B.
sang
C.
sing
D.
sings
【简答题】治疗闭经痛经宜用( )。A.生当归B.土炒当归C.酒炙当归D.当归炭A. 1 B. 1 C. 1 D. 1
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