当前位置:文档之家› Unit 4 Establishing Business Relations 建立业务关系 外贸英语函电教程

Unit 4 Establishing Business Relations 建立业务关系 外贸英语函电教程

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more /m??(r)/ adj. & pron. 更多(的) noisy /'n??zi/ adj. 吵闹的 relax /r?'l?ks/v. 放松;休息 read /ri?d/ v. 读;阅读 terrible /'ter?bl/ adj. 非常讨厌的;可怕的 feel /fi?l/ v. 感受;觉得 strict /str?kt/ adj. 严格的;严厉的 be strict (with sb) (对某人)要求严格 remember /r ?'memb?(r)/ v. 记住;记起 follow /'f?l ??/ v. 遵循;跟随 follow the rules 遵守规则 luck /l?k/ n. 幸运;运气 keep /ki?p/ v. 保持;保留 hair /he?/ /her/ n. 头发;毛发 learn /l??(r)n/ v. 学习;学会 Clark /klɑ?(r)k/ 克拉克(姓;男名) Amy /'e?mi/ 埃米(女名) Molly /'m?li/ 莫莉(女名) New York /,nju?'j??(r)k/ 纽约 Role-play John: Hi, my name’s John. It’s my first day at school. Alice: Hi, John. I’m Alice. This is a great school, but there are a lot of rules. John: Really? What are some of the rules? Alice: Well, don’t be late for class. This is very important. John: OK, so we must be on time. Can we bring music players to school? Alice: No, we can’t. And we al ways have to wear the school uniform. John: I see. Alice: Oh, and we also have to be quiet in the library.

椭圆、双曲线抛物线综合练习题及答案

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2 F C c D 1 F 9.关于曲线的对称性的论述正确的是() A.方程2 2 0x xy y ++=的曲线关于X 轴对称 B.方程3 3 0x y +=的曲线关于Y 轴对称 C.方程2 2 10x xy y -+=的曲线关于原点对称 D.方程3 38x y -=的曲线关于原点对称 10.方程 22 22 1x y ka kb +=(a >b >0,k >0且k ≠1)与方程22 221x y a b +=(a >b >0)表示的椭圆( ). A.有相同的离心率;B.有共同的焦点; C.有等长的短轴.长轴; D.有相同的顶点. 第11题 二、填空题:(本大题共4小题,共20分.) 11.(6分)已知椭圆的方程为: 22 164100 x y +=,则a=___,b=____,c=____, 焦点坐标为:___ __,焦距等于______;若CD 为过左焦点F1的弦, (如图)则?2F CD 的周长为________. 12.(6分)椭圆2 2 1625400x y +=的长轴长为____,短轴长为____, 焦点坐标为 四个顶点坐标分别为___ , 离心率为 ;椭圆的左准线方程为 13.(4分)比较下列每组中的椭圆: (1)①2 2 9436x y += 与 ② 22 11216 x y += ,哪一个更圆 (2)① 22 1610 x y +=与②22936x y +=,哪一个更扁 14.(4分)若一个椭圆长轴的长度.短轴的长度和焦距成等差数列, 则该椭圆的离心率是

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