回复：H4 volunteer at non-profit?

(iv) Spouse and dependents. The spouse and unmarried minor children of the beneficiary are entitled to H nonimmigrant classification, subject to the same period of admission and limitations as the beneficiary, if they are accompanying or following to join the beneficiary in the United States. Neither the spouse nor a child of the beneficiary may accept employment unless he or she is the beneficiary of an approved petition filed in his or her behalf and has been granted a nonimmigrant classification authorizing his or her employment.

http://uscis.gov/lpBin/lpext.dll/inserts/slb/slb-1/slb-10281/slb-16615/slb-17861?f=templates&fn=document-frame.htm#slb-8cfrsec2142h9iiic2

http://uscis.gov/graphics/services/visas.htm (see H-4)

No employment allowed, didn't mension paid or no paid. So paid and no paid are all NOT allowed.