One of the main requirements for foreign students, who want to study in the USA, is excellent knowledge of English. Students have to take the Test of English as a Foreign Language (TOEFL), and it should be prepared separately. The best way for students to learn English is to study it in the language environment.
Almost every American university language department has ESL (English as a Second Language). Set options for learning is very large - from General English (standard course, intensive, individual lessons) to such specialized programs as "work plus study", "English for study in business school," "preparation for university", "international Academic year". Starting classes is possible from any level (from beginner to high intermediate).
All major international linguistic centers such as LAL, Aspect, EF, International House, Regent and others have their branches across the United States. Many language programs involve a combination of training with the rest of American resorts. A bit cheaper than big cities is language training in small campuses, and "advanced" students can simultaneously attend university lectures. It is so-called program "Bridge Program", which is a kind of "bridge" between the university and language courses.
So, foreign students have great possibilities to study English in the USA. It will become easy for them to communicate and understand others, listen to lectures, read studying literature and write different papers. They will have no need to pay for essay.