Answer:
Your essay is good.
Explanation:
Your transition words are good. You do repeat his a lot in the writing. Sometimes it is good to repeat Jack's name instead of "his" multiple times. In a essay or any writing, you want to try to not repeat anything in it so some feedback is what I always need personally. Your conclusion sentence is good, but in the conclusions sentence you always want to kind of repeat what you said in your introduction statement, and its the same thing with saying "he," make sure you say his name. But otherwise, your essay is good! Hope this helps you!