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English definition of “on”


preposition (INVOLVEMENT)    /ɒn/ US  /ɑːn/
used to show when someone is involved or taking part in something: I'm working on a new book. In the last lesson we were on the causes of the First World War, weren't we? "Where had we got up to?" "We were on page 42."Taking part and getting involvedGetting involved for one's own benefit or against others' will Grammar:On, ontoOn and onto are prepositions.See more
(Definition of on preposition (INVOLVEMENT) from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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