It’s a rough translation, and all I really need to know is if something in it is very wrong.
Here’s the English:
The most important thing learning Chinese does for me is it opens up a new world to me. Mandarin is the most spoken language in the world, and when I learn to speak it I am able to talk to over a billion people that I couldn’t talk to before. It gives me a cultural understanding that most Americans don’t have.
It also opens up a world of literature, art, and culture. There are so many good Chinese books, movies, and works of art, and Chinese culture has had thousands of years to develop. Learning another language is something everybody should do.
And my translation:
学中文最重要的是因为我想对这个世界进行更多的了解。 中文是世界的最大的语言，和我会说中文以后我会根十亿个人说话。 我会说中文的时候，我比很多美国人懂中国的文化。
我说中文以后，我还会看中文的文学，文科，和文化。有这么多好极乐的中文电影，书 ， 和艺术，和中国的文化千年发展过。 我觉得，都人应当学别的语言。