http://www.youtube.com/watch?v=LnXUl2e2Np0

This video could be helpful. Pay attention to her lips and tounge movement for each letters. You may find lot more words other than G and Z that you may need to work on. I have seen most Nepali mess up the letter F as well...its funny how some people cannot pronounce FISH.. i have heard.. Fis, Fees, Pish, Feesh, for a FISH. The word Fish has a F vs Ph, rashwa vs dirgha,,and sano vs thulo sa/Sha issue....most folks miss atleast one of the sound on the word FISH.

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