地震现场的特点()
A.遭灾面积大、破坏严重
B.次生灾害多、灾情复杂而严重
C.伤亡人数常较多
D.现场危险大
E.需要综合救援
参考答案:A, B, C, D, E
Jobs are hard to get and, _______, more young people are continuing their education.
A.above all
B.as a result
C.on the contrary
D.after all
用20gH2与足量的O2完全反应,生成多少克水?