线路非线性效应包括以下哪些（）
A.SRS
B.SBS
C.SPM
D.XPM
E.FWM
参考答案：A, B, C, D, E
There's _____ in today's newspaper.[ ]
A. something important
B. important something
C. anything important
D. important anything
为什么要进行植物检疫？
