按发生机制,双吸气见于哪类呼吸困难
A.肺源性
B.心源性
C.中毒性
D.呼吸中枢性
E.精神性
参考答案:D
—What did Eric _____ last Sunday?
—He _____ a film with Mike. [ ]
A. do; sees
B. do; saw
C. do; was seeing
D. did; saw
滑步