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English definition of “on”


preposition (TIME)    /ɒn/ US  /ɑːn/
A1 used to show when something happens : Many shops don't open on Sundays . What are you doing on Friday ? My birthday's on 30 May. Would you mind telling me what you were doing on the afternoon of Friday the 13th of March ? Trains to London leave on the hour (= at exactly one o'clock, two o'clock, etc.). On a clear day you can see the mountains from here. She was dead on arrival (= dead when she arrived ) at the hospital . Please hand in your keys at reception on your departure from (= when you leave ) the hotel .Describing when something happened or will happen Grammar:At, on and in (time)We use at:Grammar:Other uses of in with timeWe use in to say how long it takes someone to do something:Grammar:Time expressions without at, on, inWe don’t normally use at, on or in before time expressions beginning with each, every, next, last, some, this, that, one, any, all:Grammar:At, on and in (time): typical errorsGrammar:On, ontoOn and onto are prepositions.
(Definition of on preposition (TIME) from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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