A freeloader is someone who takes food, drink, a place to sleep, or other things from people, and does not give anything in return. It is a criticising word, informal, and it started in American English in the 1930s. You would not put it on a form; you say it when you are annoyed. It is harsher than guest, and it is not a friend who comes to dinner and will cook next time. People stretch it a little: someone who never pays for drinks, who lives on a friend's sofa, who uses a company's time for their own work. Though actually, needing help is not the same as being a freeloader. The sting in the word is the feeling that the person could put something back, and will not.

白吃白住的人、愛佔便宜的人