若M=2a2b,N=3ab2,p=﹣4a2b,则下列各式正确的是[ ]
A.M+N=5a3b3
B.N+P=﹣ab
C.M+P=﹣2a2b
D.M﹣P=2a2b
答案:C
小学生概念学习发展有什么特点
In my opinion, you'd better take a couple of days off.()
A.I‘ll take your advice
B.Let me see
C.Never mind
D.I‘m afraid so