Hi,
I am Canadian, and I possess a J1 Visa which indicates that I am a trainee. I am doing my internship for a private company in USA for four months. I have the following tax questions. Please help. I am very confused by US's complex tax system.

1. What form do I file the tax with? (I think I should use a 1040 NREZ)
2. I believe US and Canada have a tax treaty. Am I exempted from paying the US tax?
3. If I am not exempted from paying the US tax, are monthly rent paid in US and meal expenses tax deductable?

Thank you for your help

1/2) You probably are exempt from U.S. taxes. Contact the payroll department of the private company you will work for; they should know the applicable article of the treaty.

3) Yes, these expenses are deductible, since the work, being less than one year in duration, is considered a temporary work assignment.