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fill in — substitute for someone

phrasal verbB2IELTS 6+neutralcommon

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

Say it like a native

Textbook I shall temporarily assume her responsibilities during her absence.

Native I'm filling in for her while she's off.

'Fill in for' is the natural workplace phrase for covering; the formal version reads like a contract.

Pattern: fill in (for [someone])

In use

  • Sarah is sick today, so I'm going to fill in for her at the meeting.work
  • Last year, I had to fill in for my manager when she was on holiday, which was a great learning experience.IELTS speaking

Common mistake

✗ Can you fill in me on Friday?

✓ 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.)

Common collocations

  • fill in for + person — for a colleague, for the teacher, at short notice, today

Don't confuse it

Not the same as 'stand in', which is more formal and less common in daily speech.

Related

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