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The best way to memorize a long passage is to just repeat it over and over. It sounds boring, and it can be, but it's going to be the quickest way. Write the passage on an index card and carry the card with you all the time. Whenever you can get someone to help, ask them to let you recite while they check you by looking at your card. If you're alone, recite to yourself and check it against the card. The more you repeat it, the better you'll remember.
If you have a long list of words or terms, the best way is to take the first letter of each word and make a Silly Sentence. Remember that "My Very Eager Mother Just Served Us Noodles" and you'll know the planets in order from the sun -- Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.
Also if you have something long to read, just make a song out of it, then when its time to read it just *say* the words instead of singing them.