左前斜位上，心后间隙消失见于（）
A.左心房增大
B.左心室增大
C.右心房增大
D.右心室增大
E.二尖瓣狭窄
参考答案：B
(2013·高考辽宁卷)He was unhappy when he sold his guitar.After all，he ________it for a very long time.
A．has had
B．had had
C．has
D．had
Only when I left my parents for Italy how much I loved them. [ ]
A. did I realize
B. I had realized
C. I realized
D. had I realized
