Phrasal Verb B1 — Intermediate

Fill In

From completing paperwork to covering a colleague's shift, fill in describes stepping into gaps — in forms and in rotas.

Quick Definition

Fill In — To complete a form with information; to substitute for someone; to inform someone of details.

Meanings of Fill In

MeaningExample SentenceExplanation
Complete a formPlease fill in the application form in block capitals.Complete all the blank spaces.
SubstituteCould you fill in for me on Thursday?Could you do my job for me temporarily?
InformFill me in on what I missed.Tell me what happened while I was away.

Example Sentences

SentenceMeaning in Context
Please fill in the application form in block capitals.Complete all the blank spaces.
Could you fill in for me on Thursday?Could you do my job for me temporarily?
Fill me in on what I missed.Tell me what happened while I was away.
"Don't worry -- I'll fill in it."Using it in a short reassurance.

Grammar Notes

Separability & Transitivity

Type: separable  |  Transitivity: transitive

Separable: fill the form in or fill in the form. With pronoun: fill it in.

How to Use Fill In

Neutral. Common in administrative and workplace contexts.

RegisterExample / Notes
Informal / SpokenPlease fill in the application form in block capitals.
Neutral / WrittenConsider context; single-word synonyms may suit formal writing.

Similar Phrasal Verbs

Practise Fill In

Practice English Phrasal Verbs

Use these exercises to master phrasal verbs in context:

Flip Tiles Find the Match Matching Pairs

Frequently Asked Questions about Fill In

What does "Fill In" mean?
"Fill In" means: To complete a form with information; to substitute for someone; to inform someone of details. It is a transitive phrasal verb rated CEFR B1.
Is "Fill In" separable or inseparable?
"Fill In" is separable. Separable: fill the form in or fill in the form. With pronoun: fill it in.
How do I use "Fill In" in a sentence?
Please fill in the application form in block capitals. -- in this example, 'Fill In' means complete all the blank spaces.
What is the register of "Fill In"?
Neutral. Common in administrative and workplace contexts.
What CEFR level is "Fill In"?
"Fill In" is typically taught at CEFR B1 — Intermediate level. It appears frequently in neutral contexts.
What is the difference between "Fill In" and similar phrasal verbs?
"Fill In" specifically means: To complete a form with information; to substitute for someone; to inform someone of details. Compare with similar verbs in the 'Similar Phrasal Verbs' section below for nuanced differences.
Can "Fill In" be used formally?
Neutral. Common in administrative and workplace contexts. When writing formally, consider whether a single-word synonym might be more appropriate for the context.
Does "Fill In" take an object?
"Fill In" is transitive. Separable: fill the form in or fill in the form. With pronoun: fill it in.
How can I practise "Fill In"?
Use LexFizz's Find the Match and Flip Tiles exercises to practise 'Fill In' in context. Seeing it in multiple sentences helps the meaning stick.
Is "Fill In" used in British or American English?
"Fill In" is used in both British and American English, though register and frequency may vary. Neutral. Common in administrative and workplace contexts.