it is pleasure for me to tell you that how much i enjoyed my stay with your family during .这句话哪里错了,为什么我看答案上说要去掉that，tell后面不是加的个宾语从句吗，为什么that不对

pleasure 改为pleasant，be后加形容词，pleasure为名词。

how 即为引导词，that重复。 tell 加宾语从句并非都是that，例如：
can you tell who is over there? 这里指“分辨得清”
i cannot tell what will happen. 这里指“断定”
另外，pleasure为名词，可加上冠词a，或者，改成 it is my pleasure to tell you how much...

很多时候that是可以省略的

pleasure改成pleased
删除that，how就是宾语从句的引导词

THAT 和HOW 重复了

pleasure 前面要加冠词，a/my之类的；that要去掉，已经有how much了

It is a pleasure for me to tell you how much i enjoyed my stay with your family during .
pleasure 是名词,前面要加冠词,另一种改法是把pleasure换成pleasant
这句话是一个宾语从句,引导词多用了一个that,画蛇添足了.

that 和 How 都可以引导宾语从句但不能同时用哈