对于多项式22t2+3t﹣1,下列说法中不正确的是[ ]
A.它是关于t的二次三项式
B.它是按t降幂排列
C.它的常数项是﹣1
D.二次项的系数是2
答案:D
Mrs Black asked us to stop _____ and listen to her. [ ]
A. talk
B. talking
C. talked
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