Practice is a critical component of a balanced GMAT test preparation program. While Master the GMAT  includes a lot of practice material (the equivalent of seven  exams), follow the links at left for even more drill. 

Each drill uses just one type of item, so you can concentrate your study on that area.  The number of questions and the time limit are intended to simulate the time pressure of the actual exam.

The best way to use these additional drills is to print them out and do them when you're off-line. At the end of each drill, is an Answer Key so that you can check your work.