by-是本族語(yǔ)的前綴，它的前身是古英語(yǔ)的bi-，其意思相當(dāng)于secondary或near by。作為形容詞性的派生前綴，它主要加綴在名詞之前，構(gòu)成新的名詞。by-是個(gè)活性詞綴，在含有by-的派生詞中，詞匯歷史較短的，往往還帶著連字符（-)。下面介紹幾個(gè)含有by-的派生詞。

bypass [ by- = secondary 次要的；pass n. 道路=>“a secondary pass 次要的道路” →]n. passage or road to one side of the main passage 旁道，旁路 / Take the bypass to avoid the traffic in the centre of town.抄旁道避開(kāi)交通擁擠的市中心吧！

bystander [ by- = near by 附近;stand v. 站立；-er n. = a person…者=>“a person who stands near by 站在附近者”→ ] n. person who stands near but does not take part 旁觀者 / The police asked some of the bystanders about the accident.警方向一些旁觀者查問(wèn)該事件。

bywork [ by- = secondary 次要的；work n. 工作=>“ secondary work 次要的工作”→] n . work done by the way, in intervals of leisure 業(yè)余工作 / He is a teacher; writing is his by work.他當(dāng)教師，寫(xiě)作是業(yè)余工作。

by-product [ by- = secondary 次要的；product n. 產(chǎn)品→]n. secondary result produced in making the main product 副產(chǎn)品 / Kerosene is a by-product of petroleum refining.煤油是精煉石 油時(shí)的副產(chǎn)品。