fill in — 2 meanings

One phrase, 2 meanings. Learn them one at a time, then test yourself.

phrasal verb2 meanings

fill in

complete a form

substitute for someone

Meaning 1 · most common

complete a form

fill in sth

to write the necessary information on a form or document.

How oftenVery common

LevelB1

Used inSpeech & writing

Examples

Please fill in this application form before your interview.

A: Do I need to fill in all these details?
B: Yes, just write your information in each box.

Common mistake

Not: Please fill the form.

Say: Please fill in the form. / fill out the form.

For forms, use 'fill in' (BrE) or 'fill out' (AmE) — bare 'fill' means make full.

More on “complete a form”Another example · Tell it apart · Goes with · Tip

Another example

In my country, when you open a bank account, you have to fill in several forms with your personal details.

Tell it apart

Fill in the form, please.

write in the details

Fill up the tank, please.

make it completely full

Goes with

fill in + form

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Next meaning: substitute for someone

Meaning 2

substitute for someone

fill in for sb

A scene showing “fill in” meaning “do someone’s job for a while”.

to do someone else's job or take their place for a short time.

How oftenCommon

LevelB2

Used inSpeech & writing

Examples

Sarah is sick today, so I'm going to fill in for her at the meeting.

A: Who's teaching our class this week?
B: Mr. Lee is filling in for Ms. Carter while she's away.

Common mistake

Not: Can you fill in me on Friday?

Say: Can you fill in for me on Friday?

To cover someone, use 'fill in FOR them'. (Bare 'fill someone in' means update them with news.)

More on “substitute for someone”Another example · Tell it apart · Goes with · Tip

Another example

Last year, I had to fill in for my manager when she was on holiday, which was a great learning experience.

Tell it apart

Can you fill in for me tomorrow?

do my job

Can you fill me in on what happened?

update me with the details

Goes with

fill in for + person

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Test yourself: which one is it?

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complete a form substitute for someone