4-（3-2x+x2）-（2x2+1）
原式=4-3+2x-x2-2x2-1
=-3x2+2x．
The reporter didn't go to bed until he finished ______ the article.[ ]
A. writing
B. write
C. to write
D. wrote
与遗精关系最密切的两个脏是
A．肝、肾
B．心、肝
C．心、脾
D．心、肾
