A:to become
B: to becoming
C: in becoming
D:during becoming
根据要求写单词。
① can not (缩写)____
② I (同类词)____
③ family (复数)____
已知正六边形的边心距为3,则它的周长是( )
抛物线y=﹣2(x﹣3)2+4的顶点坐标是____ .