ENGLISH
REFERENCE

fathom out

phr. v..
C1 Advanced Oxford

phr. v.. to finally understand something that is very difficult or mysterious after thinking about it for a long time.

phr. v.. to discern or comprehend a complex problem or mysterious situation through careful thought; often used in the negative to express total confusion.


SIMPLE

I can't fathom out why he decided to quit his job.

CONTEXTUAL

It took the detectives several weeks to fathom out how the thief had entered the building without triggering the alarm.

COMPLEX

Historians are still attempting to fathom out the exact sequence of events that led to the sudden collapse of the ancient civilization.

Particles
out
Separability
optional
Pattern
fathom + (object) + out
Usage

chiefly British English; the object can be a noun phrase or a 'wh-' clause.

Teaching tip

anchor this to the noun 'fathom' (a unit of water depth) to help students visualize 'getting to the bottom' of a deep or murky problem.

Pitfall

I couldn't fathom out it.I couldn't fathom it out.when using a pronoun like 'it', it must go between the verb and the particle because this phrasal verb is optional in its separability.

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