Dear All

Would like to know if there is any difference between: The Official Guide For GMAT Review and Official Guide For GMAT Verbal Review?

1) Are the verbal questions in the Verbal book totally different from the normal OG?
2) How is the difficulty level of verbal questions in Verbal one?
3) Is it advisable to buy the Verbal book also?

Will be really thankful if some expert could answer these questions quickly.

Thanks
Mankey