Q: "A boy in the snow riding his bike down the street." Does this mean that "There is snow on the street."?
A: yes

Q: "man riding bicycle in new york." Does this mean that "Man is repairing his bicycle."?
A: no

Q: "a man playing an electric violin." Does this mean that "man plays violin"?
A: yes

Q: "A group of men are knitting." Does this mean that "The men are knitting sweaters."?
A:
it is not possible to tell