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问题 填空题

设中心在原点的椭圆与双曲线2x2-2y2=1有公共的焦点，且它们的离心率互为倒数，则该椭圆的方程是______

答案

双曲线中，a=

1
2
=b，∴F（±1，0），e=
c
a
=
2
．

∴椭圆的焦点为（±1，0），离心率为

2
2
．

∴则长半轴长为

2
，短半轴长为1．

∴方程为

x2
2
+y2=1．

故答案为：

x2
2
+y2=1

问答题

阅读下面文字，完成试题。

        ①传统中华美食，对“油”十分讲究。 而现在，这美食中不可或缺的东西，人们却有些谈“油”色变。调查发现，我国高血脂、糖尿病、心脑血管等疾病的发病率越来越高，这类疾病的产生与人们摄入脂肪不科学有关。脂肪在体内堆积，对健康造成危害，而脂肪的来源，很大一部分就是我们平时所吃的油脂。  

         ②一边是美味大餐，却含有大量油脂，影响健康；一边是控制用油，保证健康，但味道欠佳。【甲】这似乎是难求两全的事情。【乙】人们正在寻找两全其美的办法，既享受美味大餐，又能保证身体健康。

        ③照顾到个人的饮食习惯，在高脂膳食的同时，可以考虑添加一些高膳食纤维食品。在吃大鱼大肉的同时，要有足够的膳食纤维，二者相互弥补，对人体健康较为有利。在吃油脂含量比较高的菜肴时，应该注意吃一定量的蔬菜。运用合理的膳食搭配来降低自身对油脂的摄入，在保证美味的同时，逐渐减少对油脂的依赖，从而养成良好的饮食习惯。这对很多无法拒绝美食诱惑的人，无疑是个不错的选择。

        ④人体含有多种微量元素，如一些水溶性的维生素，就像蓄水池一样，当你缺乏的时候，它可以在你身体里存留；当你不需要那么多，它就会排泄出去。但是脂溶性营养素、脂肪这类东西，如果过量地摄入，又不注意运动，它就会在体内堆积，久而久之，就会影响健康，引发疾病。

        ⑤不管是通过合理饮食达到膳食结构的平衡，还是通过运动达到人体营养摄入和释放的平衡，平衡都是我们健康生活中一个重要概念。均衡合理的膳食搭配，良好的饮食、运动、生活习惯，是我们永远的追求。只有这些达到平衡、和谐，我们才能获得强健的体魄。

阅读第②段，说出画线的【甲】【乙】两个语句不能调换的三个理由。

答：______________________________________________________________________。      

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The average age for women to marry is between 18 and 25.25 tend to (1) when somewhat older. A church wedding often (2) the legal civil ceremony, and a large reception, which often involves (3) music and dancing, is held in the evening. Wedding traditions include (4) money on the bride’s dress to represent future prosperity, the groom (5) the bride at her home, and the couple pulling on opposite (6) of a loaf of bread—whoever gets the largest piece will be (7) boss of the family. Honeymoons are a new tradition.
The principle (8) mutual support is valued in the Bulgarian family. The elderly are (9) cared for by their adult children. Unmarried adults live with their (10) and many newly married couples live with one set of parents (11) they are able to get housing of their own. Most families (12) urban areas live in apartments, which are in short
supply, while (13) in rural areas usually have their own houses. Many village houses (14) owned by families who live in urban areas, who use them_ (15) summer and weekend retreats, or for retired parents.
Most families in (16) areas do not have more than two children, while families in (17) areas tend to be larger. Grandparents play an important role in (18) care, particularly in urban areas, where most women work outside the (19) . Men of the younger generation have begun to help with household (20) , once considered only women’s responsibility.
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