properly, well
Have they been feeding you well?

poorly
The children were poorly fed.

barely
She could barely feed and clothe herself.

regularly

help (to)
How can we feed a hungry world?

afford to
He could no longer afford to feed his family.

on
She fed the children on junk food.

to
Most of the crop is fed to the cattle.

with
The animals are fed with hay and grass.

a mouth to feed
He saw the new baby as just another mouth to feed.

voraciously
The bears feed voraciously in summer and store energy as fat.

mainly, mostly, predominantly, primarily
exclusively

on
The seals feed mainly on fish and squid.

directly
constantly
Receptors constantly feed information into the system.

into
The data is fed directly into a computer.

through
This feeds the paper through to the printer.

to, with
The media were being fed with accusations and lies.

Feed is used with these nouns as the subject:
baby, calf, goose, shark, tributary

Feed is used with these nouns as the object:
addiction, animal, appetite, baby, cat, diet, dog, duck, ego, family, fantasy, fire, flame, food, frenzy, imagination, infant, meter, misinformation, myth, pet, pig