I like to know if a faxed or emailed invitation letter will be fine???????????????? i just learning of invitation letter and visa interview is next week for my friend , also , is it acceptable that my friend want to come to usa and is working in another country on work visa for 6 months but by time leaving it will be nine momths in coming for xmas????????????????? also is asking for a shorter stay better then a longer one say 5 to 7 days vist during xmas holiday but leaving before xmas to be back for xmas in the coutry there leaving from is this good ????????????