一、word study
　　request,ensure,oppose,burden,open up
　　① request n./vt.請求，要求
　　request 后面接 for，表示要求的對象；“根據(jù)要求”為 by(或 on) request；“應(yīng)。。。之要求”則 為 at sb’s request。
　　He made a request for immediate help.
　　他要求立即給予幫助。 Minibuses stop by request. 小公共汽車招手即停。
　　Instructions will be sent immediately on(upon) request.
　　說明將按要求立即寄出。
　　The singer gave one more song at our request. 歌唱家在我們的要求下又唱了一首歌。 Your silence is requested.
　　請勿說話。
　　② ensure vt.保證，擔(dān)保
　　ensure 后面接 against 或 from，表示“保證。。。免于。。�！�；后面接 to 或 for，則表示“保證。。。 具有。。。”。
　　We can ensure that the work w ill be done in the right way.
　　我們可以保證把工作做好。
　　The police can ensure the witness against (或 from) danger.
　　警察能保證證人免受危險。
　　This measure ensure to (或 for) us a voice in the matter.
　　這項措施使我們在這件事上具有發(fā)言權(quán)。
　�、� oppose vt.1、反對，反抗；2、使相對，使對抗（to）
　　Many people opposed building a new highw ay because of the great cost.
　　由于代價過于高昂，許多人都反對修一條新公路。
　　To the difficulties she opposed a will of iron.
　　她用鋼鐵般的意志對待困難。
　　What he said was totally opposed to the facts.
　　他說的與事實完全相反。
　　We are firmly opposed to this dirty political deal.
　　我們堅決反對這場骯臟的政治交易。
　�、� burden n.1、擔(dān)子，負擔(dān)；2、責(zé)任，義務(wù)
　　She bore the w hole burden of raising two children.
　　她一個人負起撫養(yǎng)兩個孩子的全部責(zé)任。
　　The burden of running the factory is too heavy for his failing health. 管理這家工廠的重擔(dān)對他日益惡化的健康來說是太重了。 vt.使負重擔(dān)；麻煩，勞累
　　The mother w as burden w ith w orries.
　　媽媽憂心忡忡。
　　Students are heavily burdened with home assignments.
　　學(xué)生家庭作業(yè)負擔(dān)過重。
　�、� open up
　　1、打開；2、開辦，開辟，開發(fā)；3、坦誠地或無拘無束地談話 They opened up his stomach to get at the source of the trouble. 他們給他的胃開了刀，以找出病根。
　　They opened up a mine in the remote areas.
　　他們在那個偏遠地區(qū)開了礦。
　　They decided to open up a business in the town.
　　他們決定在城里開一家店。
　　The girl decided to open up and tell us everything.
　　這個女孩決定坦誠地告訴我們一切。