Manhattan Prep and its top-notch GRE instructors release the most comprehensive set of GRE flash cards on the market. “500 Essential Words” is the first in a 2-volume set of flash cards.​Manhattan Prep’s GRE Vocabulary Flash Cards go above and beyond other GRE flash cards on the market. Designed help the student develop a lasting understanding of the word in a GRE-relevant context, the backs of all cards contain a word "network" with definitions, usage, synonyms, and more!500 Essential Words is the first in a 2-volume set of GRE flash cards—start with essential words and graduate to advanced vocabulary. Together, the sets comprise the most comprehensive vocabulary study tool on the market.