风心病二尖瓣狭窄发生房颤后，常见的并发症是（） A.心源性脑缺血综合征 B.动脉栓塞
题型：单项选择题
问题：
风心病二尖瓣狭窄发生房颤后，常见的并发症是（）
A.心源性脑缺血综合征
B.动脉栓塞
C.肺部感染
D.亚急性感染性心内膜炎
E.完全性房室传导阻滞
题型：单项选择题
Look ! This is a nice 1 .It’s Sunday morning. There 2 many boys and girls in the park. Some of them are singing 3 the tree. Some are 4 in the river. Other 5 are playing games on the hill.
Maria is an American girl. She is 6 to her classmates. She is in the park, too. What is she doing? She is sitting and 7 a book. She 8 _reading very much. Tom is an English boy. He is five. He is too young. He can’t 9 to school. Now he 10 a kite with his father in the park.