从方框中选择短语并用其适当形式填空。

be harmful to, at the top of, cut off, cut up, make a difference

I think the humans are _______ the food chain now.
Whatever you can do can ________ if you put your heart.
They were asked ________ unnecessary cost to save money.
The junk food ________ human health.
The boy ________ a small piece of bread and gave it to his brother.