题目内容：

It seems to be strange to you there is a blind spot(盲点)on the eyes,  Here is an interesting experiment(实验)that can make something disappear, when one eye is open.

    Make a card about the size of a postcard and write two English letters L and R on it, Lon the left and R on the right. First, hold the card about 80 cm away and you see both the letters.  Then close your right eye and look at the letter R only with your left eye. And now, as you move the card slowly towards you, you' 11 find the letter L disappearing. But if you move the card nearer to your face, the letter will be seen again. Now do the same experiment with your left eye closed, you'll find the letter R disappearing.

    Why does the letter disappear? It is because there is a blind spot on the eye. When the image（影像）of the letter falls on the blind spot,  it won't be seen.  That is why either of the letters disappears．

1.The writer of the passage thinks that_______ there is a blind spot on the eye.

A. few people know    B. no one knows C. only you know D. all the people know

2.The word "disappear" in the passage means_______ in Chinese.

A. 驱散    B．消散    C．消失    D. 遗失

3.You fail to see the letter L in the experiment because _______.

A. your eyes are poor    B. its image falls on the blind spot

C. your left eye is not open    D. you move it close to your eye

4.In which order(顺序)should you do the experiment?

①Hold the card  ②Move the card nearer  ③Close your right eye

④write two English letters  ⑤Look at the letter R  ⑥Make a card

A. ④⑥①②③⑤    B．①③⑥④⑤②

C．⑥①④③②⑤    D. ⑥④①③⑤②

5.The passage mainly tells us_______.

A. how to find the blind spot    B. an interesting experiment

C. where the blind spot is    D. there is a blind spot on the eyes.