同学你好，该知识点来自沪江网校《英语零基础直达大学六级【3年随心畅学班】》的课程，想要更系统的学习，欢迎进入课程学习。不仅可以和更多的同学一起学习，而且还有老师、助教随时的学习指导和知识点解答哦。

同学你好~

I am quite delighted to recall the last times when we went to travel in America.
可以直接写为：I am quite delighted to recall our last trip to America.

Today I am writing to plan a tour of a historical site for you.
一般写信的时候很少写Today

We will climb the Great Wall so I have a some tips for you.
a去掉

Firstly,we are going to visit the Great Wall on January 10 in winter and hence it is advisable for you to wear adequate clothes which enable you keeping warm to enjoy this trip.
which enable you keeping是错误的结构，enable sb to do
这里可以改成so that you can keep warm and enjoy the trip

For another if you can climb a little hill in advance to help you exercise,you will climb the top of Great Wall easy.
for another是“对另一个”的意思，easy是形容词，这里应该用副词。
Besides, if you can climb a hill in advance to help you exercise, you will easily climb to the top of the Great Wall.  

i am looking forward to discussing this exciting travel with you.
句子首字母要大写。

祝同学学习进步~