设点F1，F2分别为椭圆C：x29+y25=1的左、右焦点，点P为椭圆C上任意一

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问题选择题

设点F₁，F₂分别为椭圆C：

=1的左、右焦点，点P为椭圆C上任意一点，则使得

PF1

•

PF2

=2成立的点P的个数为（　　）

A．0

B．1

C．2

D．4

答案

设P（x₀，y₀），则

PF1

=（-2-x₀，-y₀），

PF2

=（2-x₀，-y₀），

由

PF1

•

PF2

=2，得（-2-x₀，-y₀）•（2-x₀，-y₀）=2，即x02+y02=6①，

又点P在椭圆上，所以

x02

y02

=1②，

联立①②解得

x0=

y0=

或

x0=

y0=-

或

x0=-

y0=-

或

x0=-

y0=-

，

故满足题意的点P有4个，

故选D．

阅读理解与欣赏

下列句子中各有一个错别字，请指出并改正。（4分）

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小题3:我知道这是暴风雨来临之前常有的预兆，我感到一种不可明状的恐惧，一种同亲人隔绝、同大地分离的孤独感油然而生。改为

小题4:美丽的心灵是任何东西都无法取代的“特长”，所以平凡的你不必自卑，即使是暗然失色的岁月，一样会被你的“特长”映亮。改为

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完形填空

My mother often asked me, “what is the most important part of the body?” Through the years I would guess at   1  I thought was the correct answer. When I was younger, I thought sound was very important to us as humans, so I said, “My   2 , Mommy.” She said, “No. Many people are deaf. But you   3  thinking about it and I will ask you again soon.”
Then last year, my Grandpa   4 . Everybody was hurt. Everybody was crying. My Mom looked at me when it was our   5  to say our final goodbye to grandpa. She asked me, “Do you know the most important body part yet, my dear?” I was shocked   6  she asked me this now. I always thought this was a game between her and me. She saw the confusion(迷惑) on my face and told me, “This   7  is very important. It shows that you have   8  lived your life”. I saw her eyes well up with tears. She said, “My dear, the most important body part is your shoulder.” I asked, “Is it because it holds up your head?”
She replied, “No, it is because it can hold the head of a friend or loved one when they   9 . Everybody needs a shoulder to cry on sometime in life, my dear. I only hope that you have enough love and   10  that you will have a shoulder to cry on when you need it.”

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