The Official Guide for GMAT Review is really the best source of verbal practice questions, as they are retired official exam questions.
A few general timing suggestions:
SC = 1:15 to 1:30
CR = 2:00
RC = 7:00 per passage with 3-4 accompanying questions.
To get faster, the two keys are (1) your process and (2) your mastery.
(1) Have a process for every question. For example, on SC, read the sentence for meaning, then scan the choices vertically and horizontally to see what words differ (i.e. to see what grammar issues are relevant.) On CR, jot some notes as you read--what are the facts given? what isn't stated, but might be important?
(2) You have mastery if you can not only pick the right answer, but explain every fault in the four wrong answers. (Do this without the timer running, by the way, perhaps after you answer the questions timed but before you check the answer and read the explanation.)
Emily Sledge | Manhattan GMAT Instructor | St. Louis
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