ENGLISH
REFERENCE

fatten up

phr. v..
B1 Intermediate Oxford

phr. v.. to make a person or animal gain weight, often by giving them a lot of food.

phr. v.. to increase the body mass or fat content of a person or animal through deliberate overfeeding; often used in agricultural or caregiving contexts.


SIMPLE

The farmer is trying to fatten up the cows for winter.

CONTEXTUAL

My grandmother always tries to fatten me up with her homemade pies whenever I visit.

COMPLEX

The livestock were moved to the lower pastures to fatten up on the lush spring grass before being sent to market.

Particles
up
Separability
optional
Pattern
fatten + (object) + up
Usage

can be used for animals (literal) or people (often slightly humorous or affectionate).

Teaching tip

this is a transitive phrasal verb that can be separated by the object; it follows the pattern of 'adjective + en' verbs like 'shorten' or 'widen' combined with the particle 'up' to show completion.

Pitfall

He wants to fat up the bird.He wants to fatten up the bird.the verb is 'fatten' (to make fat), not the adjective 'fat'.

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