fill in
phrasal verb·4 senses·particle in
Meanings
Write information into the blanks of a form
Why “in”? A person or thing enters or remains within a space, limit, activity, or feeling.
“Leo filled in a delivery form at the parcel shop.”
“Fill in the date at the top.”
Temporarily do someone else's job
Why “in”? A person, idea, effort, or item becomes part of a group, activity, or plan.
“Can you fill in for Sam tomorrow?”
“Maya filled in for the receptionist during her holiday.”
Tell someone the news or details they missed
“Fill me in on what happened.”
“Can you fill Sara in on the plan?”
Put material into a hole or gap so it is full
“They filled in the hole with concrete.”
“Workers filled in the old well with stones.”
Memory hook
You put information in each empty box.
Common mistake
Please fill the form.
Please fill in the form. / Please fill out the form.
For a form, use fill in (mainly UK) or fill out (mainly US). Fill alone means make full.
Natural collocations
The word partners “fill in” most often appears with — learn the phrase, not just the verb.
Don't confuse with
Fill in means write information into the blanks of a form. Fill out means complete a form by writing in the required information.
Test yourself
“Leo filled in a delivery form at the parcel shop.” What does it mean?
Nearby in the meaning map
Sink In connects verbs by particle pattern, contrast pairs, and shared base verbs.
fill out
A contrast learners often mix up
Complete a form by writing in the required information; Become rounder or more developed in shape; Add details to make something more complete
bask in
Same in pattern: inside
Take great pleasure in attention, success or warmth
blend in
Same in pattern: inclusion
Look or behave like the people around you
box in
Same in pattern: inside
Surround tightly with little room
break in
Same in pattern: inclusion
Enter a building illegally by force; Interrupt a conversation and begin speaking
bring in
Same in pattern: inclusion
Introduce someone or something into a discussion or organisation; Earn money for a person or business; Introduce a new law, system or rule; Deliver a verdict in a court
chain in
Same in pattern: inside
Hold someone or something in place using chains
check in
Same in pattern: inside
Register at a hotel, airport or event; Hand over luggage to be loaded onto a plane; Briefly contact someone to update them
Tell it apart
Side-by-side comparisons with the verbs learners most often confuse for “fill in”.
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