How can I write better essays?

How can I write better essays?
I am high school sophomore living in Puerto Rico. I really want to do well in the SAT and essay. How can I overcome the language barrier and write good essays? I can speak English , Korean, and Spanish.

First of all: congratulations, at highschool not everyone can speak three lenguages, and three this much different ones. You must have a good sence of lenguage learning and literature, just have to practice some skills. If you want to make it professional level you mgiht try buying some books, but there are soem quick tips ive learnt along the years:
1.practice a lot, pick themes for yourself, starting from expressing your oppinion or describing a festival, anything YOU ARE INTERESTED IN, that youve liked, and then write essays for yourself. If you create a motivation for practising by yourself youve taken the most important step. Decide depending on your schedule that you will write two-three essays per week or so, and then do it. Each week after you have completed it take soem reward for yourself, chocolate, or a nice two hours with your friends.
2.Always start your essay with brainstorm. It takes only five to ten minutes and it will make up thousand time during your exams. Write down the topic on a piece of peper, and and write beside it everything that come to your mind from it ex topic: environment, ideas: greenhouse effect, cars, pollution, airplanes, green areas in towns, diseases, asthma, ocean, endangered animals etc. If you cant enumerate many, then write a couple of aditional ideas on the first ideas: ex ocean-> endangered whales, dolphins, ship crashes, diversity, coral reefs ets.
3.After you have completed it do take five more minutes taking notes, constructing your essay, helps you link the ideas , you would know how to include them one after the other. ex: environment->air pollution (airplanes, cars, dust, smog, London, diseases, asthma)->water pollution( major sourse of life,whales, oil, corals, fish, food)-> soil pollution(trees, rainforests etc).
4.Think of a very interesting title: that will draw attention, and will be a good start. ex: dont start with : Environment, but soemthing like: Will human race survive? (ok, a bit melodramatic, but that was what came to my mind, and a melodramatic title is always better then a boring one)
5.Start and end with general ideas. In the first couple of sentences refer to the title, explain it, draw curiousity closer to yuor own subject.
6.Dont forget that essay is developing an idea without reaching for the totality of the subject, and that is a great help. End with sentences that bring up more questions, or stress on the idea that the subject is not closed yet. Another good idea is to quote someone famous about the issue. that might be looking hard, and many ask how can you bring up a quotation to everything, but as youre practising many subjects will come up, and in a couple of weeks youll get to know a couple of nice sentences of famous people, that can be applied. It is highly probable that you will all the subjects that will arrive at any exam in the future.
7.Want to know a secret?:) Your passive vocabulary is at least ten times wider then your active one, menaing the words you understand but dont generally use are lot lot more. Use monolingual vocabulary to them, and the most important thing: READ READ READ. The first book is the hardest, and with reading five-six novels you will experience at least two to four times larger vocabulary.
8.Keep enjoying it. If you like it, your brain works lot better, and that will be like a walk in the park. Good luck!