these days i recite GRE words,but i think it's very dificult,vevry unit is about 200 words.

GRE is short for Graduate Record Examination. It is a coercive test for admission of American Graduate Schools usually. As a result, if you want to apply for Graduate Schools in US, you have to take GRE. Besides, TOEFL is needed if your native tongue is not English. Except America, there are many other graduate schools in the world also need the appliant to provide his/her GRE score, for example universities in Singapore or Canada.
For someone whose native language is not English, and during his study process, he was taught in other languages other than English, I think it is a huge program for him to prepare for the GRE.

http://www.syvum.com/gre/ (GRE Test Preparation)
http://ets.org/portal/site/ets/menuitem.1488512ecfd5b8849a77b13bc3921509/?vgnextoid=d683919ac3ca5010VgnVCM10000022f95190RCRD&vgnextchannel=7aff2ce292885010VgnVCM10000022f95190RCRD (Also test materials download)

To me, GRE is the test you should take if you want to apply for a scholarship for masters or doctors in the US. As far as I know, a lot of people are reciting the GRE Vocabulary book as a start.