Thank you very much..... this is the first time I know about GRE and I have to master it in a month because I will hold the test in early of September. That's very hard but I will try my best. Once again, great thanks :)

My experience goes a long way back in time so I do not think it is relevant in your case. I would propose that you go ahead and purchase the official tests provided by the ETS. In my opinion it will be money well spend. GRE Verbal is always the hardest for foreigners. http://www.ets.org/gre/revised_general/prepare/?WT.ac=grehome_greprepare_c_150213 Best of luck.

I know and I will pursue my master in Health informatics

You do know in GRE you are competing with native English speakers for entry in graduate school. How familiar are you with GRE. Which graduate school field of study are you planning to apply for?