()1,,2
A.
B.0
C.
D.
参考答案:B
解析:
各项依次为,根号下是连续自然数。
John, may I use your computer now?
Sorry, it is not ____at the moment. It is being repaired.
A.convenient
B.valuable
C.available
D.comfortable
动手术切除翳膜的条件是什么?