ENGLISH
REFERENCE

fill in for

phr. v..
B1 Intermediate Oxford General-service

phr. v.. to do someone else's work for a short time because they are away or sick.

phr. v.. to act as a temporary substitute for someone; typically used in professional or social contexts to denote a short-term replacement.


SIMPLE

Can you fill in for me while I'm at the doctor?

CONTEXTUAL

The assistant manager had to fill in for the director during her three-week maternity leave.

COMPLEX

Despite having little experience in logistics, Sarah was asked to fill in for the department head during the emergency summit.

Particles
in for
Separability
inseparable
Pattern
fill + in + for + object
Usage

usually followed by a person; implies the substitution is temporary.

Teaching tip

contrast with 'stand in for' (very similar) and 'replace' (which often implies a permanent change); 'fill in' without 'for' can also mean to complete a form.

Pitfall

I will fill in for his job.I will fill in for him.you fill in for a person, not for a task or a position; you 'fill' a position but 'fill in for' a colleague.

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