by the time l got there,the plane ...(leave) already.用所给动词的适当形式填空

问题描述:

by the time l got there,the plane ...(leave) already.用所给动词的适当形式填空

by the time l got there,the plane (had left ) already.
根据前半句,可知用过去完成时‘ 表示过去的过去已经完成或发生了的动作’
加油!不明白再问!