# up to sth

CEFR B1 · Phrasal verb

Source: https://englishreference.com/word/up-to-sth
Updated: 2026-04-24

## Definition

to be doing something, especially something secret or bad.

For teachers: to be occupied with or engaged in an activity; frequently carries a negative prosody implying mischief, secrecy, or illicit behavior.

## Examples

- What are those kids up to in the garden?
- He looks very guilty, so I am sure he is up to something he shouldn't be doing.
- The investigators suspected the firm was up to some creative accounting to hide their recent losses from the shareholders.

## Pitfalls

- Not "What are you up to do?" but "What are you up to?" — the phrase functions as a predicate adjective or phrasal verb and does not take an infinitive verb after 'to'.

## Usage notes

- usually used in questions or with indefinite pronouns like 'something', 'anything', or 'nothing'.
- Teaching tip: distinguish between the neutral 'What are you up to?' (meaning 'What are you doing?') and the suspicious 'What are you up to?' which implies mischief based on tone and context.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.