题目

用方框中所给单词的适当形式填空。game, fifth, happy, old, sister （1） My classmate John has soccer balls. （2） January 19th is my birthday. （3） Hi, Grace! You look very . （4） The two basketball are in October. （5） Here is an photo of my grandmother. 答案：【1】five 【1】sister's 【1】happy 【1】games 【1】old若多项式3x2+kx-x-1中不含有x的一次项，则k=_________．