To eat up is to eat all of some food or all of a meal you have been given.
Examples of use:
1. The baby ate up all of his pasta today.
2. Eat up your cabbage. It’s good for you.
When something eats up something else; for example, time or money, it uses it all.
Examples of use:
1. The housework eats up my spare time at weekends.
2. The electricity bill has eaten up all my wages this month.
infinitive – eat up
present simple – eat up and eats up
-ing form – eating up
past simple – ate up
past participle – eaten up
See also, eat out
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