曾因犯罪受过刑事处罚或者曾被开除公职的人，只要改过自新，仍然可以报考人民警察。 ( )
参考答案：错
We hope the measures to control prices, _____ are taken by the government, will succeed. [ ]
A. as
B. when
C. since
D. after
氧气的化学性质有哪些？
