My suggestion would be to stick to official content for Verbal Section.
Start with the recent Official Guides and then move backwards. You will have official guide 2017,16,15 Official Guide 12th ed, 11th ed and 10th ed; Verbal review 1st ed., 2nd ed, 2016, 2017.....Once you are done with these go for Question Pack from mba.com.
This material should be sufficient and set you up for the exam. Once you are done with this then go for
MGMAT questions. Do not go beyond this. Any questions coming from non-official source will do you more harm than good.