Sounding the same, but spelled differently:
* hare/hair: A hare is a rabbit-like mammal, while hair is the growth on your head.
* doe/dough: A doe is a female deer, while dough is the mixture used to make bread.
* grate/great: A grate is a metal grid, while great means something impressive. (You might grate cheese on a grate, or have a great time at the zoo.)
* deer/dear: Deer are animals, while dear means beloved.
* ewe/you: An ewe is a female sheep, while you is a personal pronoun.
Sounding similar, but spelled differently:
* ant/aunt: An ant is an insect, while an aunt is a relative.
* bear/bare: A bear is an animal, while bare means without anything covering it.
* flea/flee: A flea is a tiny insect, while flee means to run away.
* seal/seel: A seal is a marine mammal, while seel is an archaic word for "to see" (not commonly used).
Note: Some of these homophones have multiple meanings, but the animal meanings are listed above.