You are going to spend two years on a small tropical island.
No people, no house, no buildings,no roads...are on the island .
there be 是倒装句，未必什么时候用都好
改成正常语序，更朗朗上口
You will be living there alone. You cannot leave the island.
The island is covered by jungle , and any large or dangerous animals don't appear to be there .
树与丛林重复，删除trees
appear 多用主动语态
There are lots of fruit trees and there is a well which supplies plenty of fresh water.
When you come to the island before , you must get all your necessary clothes .
必要的衣服，可以用一个necessary 单词，而不是一个冗长的定语从句
准备服装多是在出发前，需要加入before
there are 与复数
there is 与单数
Besides, you will be given enough packaged food for two months.
You have to make a list of EIGHT other items to take with you to help you survive.
You can take more than one of any itms
这句话感觉上下文不连贯，是不是可以去掉
For example: some books, some knives, etc.
All the items must fit in a small boat.
In the next class , you will talk about what items you have chosen, why you need them, and what will you use them for.
have to 情态动词，过于强硬，需要删除
In the next class这个找不到上下文，没有第一节课，何来第二节课？
what will you use them for
这个will要提前，语法错误
你需要注意英语思维，
此文汉语化很严重
《高等学校英语应用能力提高系列：英汉翻译技巧与实践》
这本书你可以看看体会汉语思维与英语思维的区别