能反映急性呼吸窘迫综合征(ARDS)的典型症状是()。
A.脉搏浅快
B.血压下降
C.心律不齐
D.进行性呼吸困难
E.出现神经精神症状
参考答案:D
用下列词的适当形式填空。
1. He's too old. He can't run _______ (quick).
2. She's very careless. She can't do her lessons _______ (careful).
3. Little Tom is often late for class. His teacher is quite _______ with him. He said to him _______, "Don't be
late again." (angry)
4. It's dark in the room. Can you see these pictures _______ enough (clear)?
5. Listen, the children are playing games _______ (noisy).
6. There was a _______ rain last night. When I got home, it was raining _______ (heavy).
7. Please take _______ care of the little bird. It can sing _______ (good).
8. Walk _______ in the library, you should keep _______ (quiet).
若x m+2n=16,xn=2,(x≠0),求x m+n的值