How character contribute to the story.

I have an assignment to write an essay about how the characters contribute to the story. The essay has to be within 300 words, but my essay went beyond of that. The thesis statement has to have the key point, how the characters contribute to the story. I chose the story Two Kinds by Amy Tan.
I chose a mother in the story, and I think her existence is bigger than her daughter who is a narrator of the story. Please give me an idea how I should improve my writing. Also, please help me to correct my word-choosing and grammar mistakes because I feel my writing somehow doesn't make sense for the people in the United States. Thank you very much!!

Jing-Mei's mother in Two Kinds, the story by Amy Tan, is a very important character who has the power to dominate the story. Jing-Mei is a narrator who tells readers her perspective and thoughts, so the author makes the readers to believe that she is the one who influences the entire story. As a matter of fact, the author wants the readers to realize the mother is both round and dynamic character, and each of her action is very impressive and has a link to the climax of the story.

The first impression of the mother is that she is a dedicated mother who only considers to educate her daughter. Chinese government puts priority in the education, so China has a slogan, "gearing education to modernization, to the world, and to the future." Since the mother is from China, this slogan puts the role of the mother outside the concept of how the United States educates children. In the United States children do not have to prove who he or she is when they are young. The mother tells her daughter to study various things intensively to become a Chinese Shirley Temple, a prodigy. Since then, each of the mother's commands and emotions become the power to put her daughter's life in risk. Eventually, this cultural difference gives the daughter misunderstanding, pressure and insecurity, and it makes her not to try on anything. Thus, the mother opens the door of the prison, which is created by the mother to be cruel to her daughter, and lets her daughter whatever she wants to do. At the climax of the story, the mother leaves an invisible message with a present when the daughter's thirtieth birthday. This message reminds Jing-Mei what she has done in the past and tells her that let go of the past regret and future concert and try to live in the present as much as possible.

In conclusion, the invisible message that Jing-Mei's mother gives her daughter in the climax is the key of the story. The invisible message is not the torture to sink her daughter the depths of grief and is not even the meaning of the mother is a failed mother. The interpretation of the message is that it is not too late to put a start line even though she is thirty years old. Once she finds what she wants to be, do not stray from the path where she has to go.