1 B1 neutral
Of a structure such as a roof or ceiling: to collapse inward.
"Years of neglect had weakened the barn roof, and it finally fell in after the heavy snowfall."
inseparable
fall in
B1 neutral inseparable intransitive
To collapse inward, or to form a military line on command.
In plain English
To cave in and collapse, or to stand in a straight line as soldiers do.
What does "fall in" mean?
2 meanings, ordered from most common to least. Color-coded by CEFR level.
2 B1 idiomatic neutral
Military: to form ranks; to line up in an ordered formation on command.
"The sergeant shouted 'Fall in!' and the recruits scrambled to form a straight line."
inseparable
Literal vs figurative
Words literally mean
To fall toward the inside or interior of something.
Actually means
To cave in and collapse, or to stand in a straight line as soldiers do.
Usage tip
In military contexts, 'fall in!' is a direct order for soldiers to form ranks. In structural contexts, it describes a roof or surface collapsing inward. Both uses are clear from context. The military sense is well known even among civilians from films and TV.
Words that pair with "fall in"
Natural word combinations native speakers use most often.
roof ceiling soldiers troops ranks formation parade
How to conjugate "fall in"
The five tense forms you'll use most often.
Base
fall in
I/you/we/they
3rd person
falls in
he/she/it
Past simple
fell in
yesterday
Past participle
fallen in
have + pp
-ing form
falling in
continuous
Hear "fall in" in the wild
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Other ways to say "fall in"
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