舒张早期奔马律（）。
A.扩张型心肌病
B.二尖瓣狭窄
C.缩窄性心包炎
D.轻中度肺动脉瓣狭窄
E.二尖瓣脱垂
参考答案：A
“公安三袁”是指哪三个？
He added a ______ to his letter by saying that he would arrive before 8 pm.
A. presidency B. prestige C. postscript D. preliminary
