ENGLISH
REFERENCE

be up to

phr. v..
B1 Intermediate Oxford

phr. v.. to be doing something, especially something secret or bad.

phr. v.. to be occupied with or engaged in an activity; frequently carries a pragmatic implication of mischief, secrecy, or illicit behavior.


SIMPLE

What are you up to this weekend?

CONTEXTUAL

The children are very quiet, which usually means they are up to no good.

COMPLEX

The investigative journalist spent months trying to discover what the corporation was actually up to behind closed doors.

Particles
up to
Separability
inseparable
Pattern
be + up + to + object
Usage

often used in questions to ask about plans or in the phrase 'up to no good'.

Teaching tip

note that this phrase has multiple senses; focus on the 'doing/planning' sense first before introducing the 'be capable of' or 'be the responsibility of' senses.

Pitfall

What are you up to do?What are you up to?the phrase functions as a complete predicate; you do not need to add the verb 'do' after it.

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