英语——把两个句子合并成一个定语从句
问题描述：
英语——把两个句子合并成一个定语从句
They have just started their trip to Tibet.They prepared for it for about a month.
答
They have just started their trip to Tibet.They prepared for it for about a month.
= They have just started their trip to Tibet (which/that) they prepared for for about a month.
= They have just started their trip to Tibet for which they prepared for about a month.
注：（ ）表示可以省略不用；/ 表示可以任选其一.