These questions are similar to the SAT verbal reading comprehension questions. There are no analogies or antonyms however. Also, this is not a test of vocabulary. In general, it is worthwhile to write your answer in a simple, straightforward format with a clear topic sentence, transition sentences, etc. Many MIT students prepare for the MCAT by taking a commercial test preparation class offered by Kaplan or Princeton Review.
Additional materials published by third-parties are available in most bookstores.
This way, if you are dissatisfied with your score, you may retest in April without delaying your application. The test may be taken in the August of the senior year, however the delay in reporting your scores may affect your chances of admission. Your premed advisor will write the cover letter for all your other letters of recommendation. This letter may be a simple summary of what has been said in the other letters or it may include other information about you. Some advisors are MIT professors in the sciences or humanities, others are practicing physicians.