This page can help you a lot while you are practicing for the exam, here you can find some tense tutorials - formation and usage :(http://www.englishpage.com/verbpage/simplepresent.html),for more tenses just klick the name of the tense on the left.

For Passive formation visit this page:http://www.ego4u.com/en/cram-up/grammar/passive

For exercising tenses usage klick: http://www.englishpage.com/verbpage/verbtenseintro.html

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