previous与before的区别是？从意思上去区别它们

    Previous 多用作形容词，而before 是介词、连词、副词。previous /ˈpriːvɪəs/ CET4 TEM41。ADJ A previous event or thing is one that happened or existed before the one that you are talking about。
     前一次的例：She has a teenage daughter from a previous marriage。她有个出自前一次婚姻的十几岁的女儿。2。ADJ You refer to the period of time or the thing immediately before the one that you are talking about as the previous one。
     前一个的例：It was a surprisingly dry day after the rain of the previous week。这是继前一周的降雨之后出奇干燥的一天。
  before /bɪˈfɔː/ CET4 TEM41。PREP If something happens before a particular date, time, or event, it happens earlier than that date, time, or event。
     在 (某日、某时、某事件) 以前例：Annie was born a few weeks before Christmas。安妮在圣诞节前几个礼拜出生。Before World War II, women were not recruited as intelligence officers。
    二战前，女性不被征募为情报官。2。CONJ Before is also a conjunction。 在 (某日、某时、某事件) 以前例：Stock prices have climbed close to the peak they'd registered before the stock market crashed in 1987。
    股票价格已经快爬升到了1987年股市崩溃前的最高纪录。3。PREP If you do one thing before doing something else, you do it earlier than the other thing。
   在 (做某事) 之前例：He spent his early life in Sri Lanka before moving to Canada。  移居加拿大前，他早年生活在斯里兰卡。
  4。CONJ Before is also a conjunction。 在 (做某事) 之前例：He took a cold shower and then towelled off before he put on fresh clothes。
    他穿上干净衣服之前，冲了个冷水澡，再擦干身子。5。ADV You use before when you are talking about time。 For example, if something happened the day before a particular date or event, it happened during the previous day。
     (某时、某事) 以前例：The war had ended only a month or so before。战争大约在一个月前才结束。6。PREP Before is also a preposition。
   (某时、某事) 以前例：It's interesting that he sent me the book twenty days before the deadline for my book。
    有趣的是，在距离我书的截止日期20天前他把那本书寄给了我。7。CONJ Before is also a conjunction。 (某时、某事) 以前例：Kelman had a book published in the U。
  S。 more than a decade before a British publisher would touch him。  科尔曼在美国已经出版了一本书，十多年后英国的出版商才愿意出版他的作品。
   词性不一样，你看看词性 一个是形容词一个是连词，介词，副词 你给我讲个例子，什么叫从意思？。