题目

观察下列各式:①abx-adx;②2x2y+6xy2;③8m3-4m2+2m+1;④a3+a2b+ab2-b3; ⑤(p+q)x2y-5x2(p+q)+6(p+q)2;⑥a2(x+y)(x-y)-4b(y+x).其中可以用提公因式法因式分解的是( ) A.①②⑤                B.②④⑤ C.②④⑥                D.①②⑤⑥ 答案：D.①abx-adx=ax(b-d);②2x2y+6xy2=2xy(x+3y);③8m3-4m2+2m+1不能用提公因式法因式分解;④a3+a2b+ab2-b3不能用提公因式法因式分解; ⑤(p+q)x2y-5x2(p+q)+6(p+q)2=(p+q)[x2y-5x2+6(p+q)];⑥a2(x+y)(x-y)- 4b(y+x)=(x+y)[a2(x-y)-4b].所以可以用提公因式法因式分解的是①②⑤⑥.根据中文提示完成句子。【1】中国人民欢迎全世界的游客。Chinese people ______ the ______ from all over the worlD.【2】我的妹妹有个健康的饮食。My sister has ______ ______ ______.【3】下个月请帮我照顾我的两只小狗。Please help me take ______ ______ my little dogs next month.【4】我打算在八月去北京。I will go to Beijing ______ ______.【5】我爸爸下周一将给我寄一些钱。My father ______ ______ some money ______ me next Monday.