Although “The Official SAT Question of the Day” is not meant as a teaching tool for university students, it happens to offer excellent exercises for testing and improving your knowledge of English grammar and vocabulary (as well as mathematical thinking).  There’s good variety to the questions, and you can gain a lot with a small effort: just one question a day.  Try it.  Here’s the link: http://sat.collegeboard.com/practice/sat-question-of-the-day

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