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English definition of “by”

by

preposition (METHOD)    /baɪ/
A2 used to show how something is done: They travelled across Europe by train/car. She did the decorating (all) by herself (= alone, without help from anyone). We went in by (= through) the front door. Do you wish to be paid in cash or by cheque? He learned English by listening to the radio. Suddenly, she grabbed him by the arm (= took hold of this part of his body). I refuse to live by (= following) their rules.Ways of achieving things Grammar:ByBy is a preposition or an adverb.See moreGrammar:By and timeWe use by meaning ‘not later than’ to refer to arrangements and deadlines:See moreGrammar:By and the passiveWhen we use the passive voice, we can use a phrase with by to say who did the action:See moreGrammar:By meaning ‘how to do something’We use by + -ing form to describe how to do something:See moreGrammar:By + myself etc.When we say by + myself, yourself, himself, herself, itself, oneself, ourselves, yourselves, themselves, it means ‘alone’. We sometimes use all for emphasis:See moreGrammar:By and placeWe use by to mean ‘beside’ or ‘at the side of’:See moreGrammar:By and measurements and amountsWe use by to talk about measurements, and increases and decreases in amounts:See moreGrammar:By meaning ‘during’We sometimes use by + day and by + night to mean ‘during the day or the night’:See moreGrammar:By meaning ‘written’ or ‘composed’We use by when we talk about the writers of books, songs, poems, symphonies, etc.:See moreGrammar:By: typical errorsSee more
(Definition of by preposition (METHOD) from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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