| 词组 | before conjunction |
| 释义 | Contents overview before : conjunction250 before: conjunctionbefore + clause, + clauseclause + before + clause1use and positionBefore and its clause can come either before the main clause (often with a comma) or after. Putting it at the end can give it more importance in information structure (267). Before I have breakfast, I go for a walk.I go for a walk before I have breakfast.Note the time relations: in both cases the speaker goes for a walk first and then has breakfast. Compare:I have breakfast before I go for a walk. (The speaker has breakfast first.)2present or present perfect tense with future meaningWith before, we use a present or present perfect tense if the meaning is future (231).I'll telephone you before I come. (not … before I will come.)We can't leave before the speeches have finished. 3perfect tensesIn clauses with before, we often use present perfect and past perfect tenses to emphasise the idea of completion.You can't go home before I've signed the report. (= … before the moment when I have completed the report.)He went out before I had finished my sentence. (= … before the moment when I had completed my sentence.)(Note that in sentences like the last, a past perfect tense can refer to a time later than the action of the main verb. This is unusual.)4before things that don't happenWe sometimes use before to talk about things that don't happen (because something stops them).We'd better get out of here before your father catches us.She left before I could ask for her phone number.5before …ingIn a formal style, we often use the structure before + -ing.Please turn out all the lights before leaving the office.Before beginning the book, she spent five years on research.For before as an adverb and preposition, 396–397.For before and ever, 454.4.Previous Next |
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