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sit up - definition and synonyms


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phrasal verb
Word Forms
present tense
I/you/we/theysit up
he/she/itsits up
present participlesitting up
past tensesat up
past participlesat up
  1. 1
    [intransitive/transitive] to go from a lying position to a sitting position, or to help someone to do this
    Would you like to sit up and read for a while?
    We sat her up in a chair.
  2. 2
    [intransitive] to sit straight and not bend or lean
    sit up straight: You’ve got to stop slouching and sit up straight.
  3. 3
    [intransitive] British to go to bed later than usual
    We sat up very late talking last night.
See also main entry: sit


a course of study which is much shorter than a university course and focuses on the skills you need for a job, especially computer-related skills

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an ancient Roman system of underfloor heating, used to heat houses with hot air; from the Latin 'hypocaustum'

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