定语从句并没有固定的时态规律.主从句时态都要根据具体情况而定.
eg.I will eat the food you bought yesterday.主将从过去
I bought the same book this morning as you bought yesterday.主过去,从过去.
I liked the way you spoke English,主从都是一般过去时.
I have finished all the work that you asked me to do.主句现在完成,从句一般过去.
I finished all the work that you had asked me to do.主句一般过去,从句过去完成.
没有规律,没有限制.主从句各自的时间状语对应各自的时态.
希望能帮倒你.