题目

梨、桃等的栽培通常用 来繁育优良品种(   ) A.嫁接 B.种子 C.扦插 D.压条 答案：AI ___________in the No.8 Middle School for three years, and I have been in this school for one and a half years.A. have studied B. had studiedC. studied D. was studying