E

 early on = early; at the beginning of something.

Early on in their relationship, Donna and Bill ate lunch together every day.

 eat away at = to cause trouble, create worries.

Problems at work are eating away at him so much, he can’t sleep at night.

Don’t let your daily worries eat away at you. Take one day at a time.

 eat out = eat at a restaurant

eat in = eat at home

He eats out a lot because he works late at night. Eating in is healthier.

 eat up = eat everything

This boy is going to eat up all these french fries before his brother has a chance to eat any.

 end up = finish; final destination or result. Also, end up with

Originally, they had planned to go out to eat, but then they ended up watching TV.

He ended up with a good wife who always supported him.