feed on／upon
1．live on； take as food以…为食物
Cattle feed chiefly on grass．牛主要以草为食。
What do you feed your dog on？你用什么喂你的狗？
We feed our dogs on fresh meat．我们用新鲜的肉喂狗。
He is out of employment and feeds on a friend．他失业了，靠朋友生活。
2．become nourished，satisfied or strengthened from；consume or utilize from从…得到供养、满足、增强；以…为能源
His convictions feed on determination．由于有了决心，他的信心增强了。
The eye feeds on beautiful objects．美景悦目。
The gas turbine feeds on the fuel it pumps．燃气轮机以它抽入的燃料为能源。