Set three bottles of 10 7 3 as ab C. Fill bottle B, then bottle C with honey, and then pour bottle C back into bottle A. After two times, there is 1 kg left in bottle B of 7 kg, and bottle A has 9 kg. Pour 1kg into bottle C, then put 9 kg into bottle B, leave 2 kg in bottle A, put 5 kg into bottle B, and leave 5 kg for another person to take away.