before的详细用法

before的详细用法

Before 在英语中是一个比较常用的虚词,它既可作介词或副词用,也可作从属连词用.在近几年的高考试题中常常出现考查其从属连词用法的题目.下面就把其作为从属连词的用法归纳如下：1.表示“在…..之前就…..”.Mary had finished her homework before her mother returned.2.表示“过了多久后才……..,动作进行到什么程度才……”The man almost knocked me down before he saw me .They walked about 30 miles to the west before they saw a village .They worked day and night about three days before everything returned to normal .3.表示“来不及； 尚未…..就…” Before I could get in a word ,he had measured me .He ran off before I could stop him .She left the company before I could have a word with her .4.表示“刚…就…”I had hardly sat down before the bell rang.5.表示“不知不觉就…..； 还没弄清就……”Time passed quickly and three months went by before Aqiao knew it.6.表示“宁愿…,决不…,与其…,毋宁….”常与will 或would 连用.I would die before I would tell I’d shoot myself before I apologized to him.I would / will die before I surrender .7.表示“否则；以免”Do it now before you forget .I will write it down before I forget it .8.用于句型“it was +时间段+ before …” 表示 “过了多久才…”It was three days before he came back..9.用于句型 “ it was not long +时间段+ before …” 意为“不久就….”It was not long before he sensed the danger of the position .10.用于句型“it will be(not )+时间段+ before….”表示“要过多久/ 不久…才…”It will be half a year before you graduate from this school .It will be not long before you find you are wrong .

这个解释是对的