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English definition of “if”


conjunction (REQUEST)    /ɪf/
used when you want to make a polite request or remark: If you'd like to take a seat, Mr Chang will be with you in a moment. Would you mind if I open/opened (= can I open) the window? There are, if you don't mind me saying so, one or two problems with this plan.Connecting words which express a condition Grammar:IfIf is a conjunction.See moreGrammar:If or when?We use if to introduce a possible or unreal situation or condition. We use when to refer to the time of a future situation or condition that we are certain of:See moreGrammar:If: conditionsWe often use if to introduce possible or impossible situations or conditions and their results. The situations or conditions can be real, imagined or uncertain:See moreGrammar:If possible, if necessaryWe can sometimes leave words out after if to form fixed expressions:See moreGrammar:If so, if notWe use so or not after if when it is obvious what we are referring to:See moreGrammar:Even ifWe can use even if to mean if when talking about surprising or extreme situations:See moreGrammar:If: reporting questionsWe use if to introduce reported yes-no questions and questions with or.See moreGrammar:If and politenessIn speaking, we often use if to introduce a polite request. If is usually followed by modal verbs will, would, can or could when it is used to be polite:See moreGrammar:When or if?We use when to refer to a future situation or condition that we are certain of, whereas we use if to introduce a possible or unreal situation.See more
(Definition of if conjunction (REQUEST) from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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