排污费征收程序一般分为哪几个主要环节。（）
A.排污申报登记
B.排污申报登记审核
C.排污收费计算
D.排污费征收与缴纳
参考答案：A, B, C, D
Some students are seen doing _______ work they can find to support themselves. [ ]
A. whichever
B. no matter what
C. whenever
D. whatever
