阅读短文，从方框中选择适当的句子还原到短文中，使短文意思完整．
Scientists think that many or most animals can't see colors．【小题1】 ．To find out if dogs could see colors，scientists gave dogs food every time they played certain piece of music．  【小题2】 only when they heard this piece of music．They did not get ready to eat when they heard other pieces of music．
Then the scientists gave the dogs food every time they showed them a certain color．The dogs got ready to eat when they saw thi s color． 【小题3】 ．Again the dogs got ready to eat．The colors were al l the same to them．  【小题4】 ，however．For example if  we put food in a red box and do this every day．A monkey wiIi always go to the red box to get the food．  【小题5】 if we then put food in a blue box．

阅读短文，从方框中选择适当的句子还原到短文中，使短文意思完整．

Scientists think that many or most animals can't see colors．1. ．To find out if dogs could see colors，scientists gave dogs food every time they played certain piece of music．  2. only when they heard this piece of music．They did not get ready to eat when they heard other pieces of music．

Then the scientists gave the dogs food every time they showed them a certain color．The dogs got ready to eat when they saw thi s color． 3. ．Again the dogs got ready to eat．The colors were al l the same to them．  4. ，however．For example if  we put food in a red box and do this every day．A monkey wiIi always go to the red box to get the food．  5. if we then put food in a blue box．

    阅读短文，从方框中选择适当的句子还原到短文中，使短文意思完整．

    Scientists think that many or most animals can't see colors．  1  ．To find out if dogs could see colors，scientists gave dogs food every time they played certain piece of music．  2  only when they heard this piece of music．They did not get ready to eat when they heard other pieces of music．

    Then the scientists gave the dogs food every time they showed them a certain color．The dogs got ready to eat when they saw thi s color．  3  ．Again the dogs got ready to eat．The colors were al l the same to them．  4  ，however．For example if  we put food in a red box and do this every day．A monkey wiIi always go to the red box to get the food．  5  if we then put food in a blue box．

1．____________  2．___________  3．___________4．_________  5．____________

A smile will tell people around you that you are a kind and friendly person. However, many people don’t smile because they think they ugly teeth. For example, one of my classmates, Mile, doesn’t have very nice teeth, so that is why he seldom opens his mouth. he even says that he has lost confidence because of his teeth. So it is very important for us to look after our teeth. In fact, a lot of people have this problem. Some people inherit teeth problems from their parents, while others’ teeth are damaged because of bad habits, like heavy smoking, eating too much sugar or not brush-ing teeth often. If your teeth are in bad shape, you should see a dentist and ask for help. They can help improve your teeth and tell you how to take care of then.
Smiling can help you to feel more confident and make other people think of you as a more friendly person. If you want to keep healthy, you should not only smile but also laugh. An Indian doctor called Katarina said that young children should laugh about 300 times a day, wile adults should laugh between 7 and 15 times a day. So please take this chance to smile and laugh now!
根据短文内容，选出一个最佳答案填入题前括号内。
1. What has made Mike lose his confidence?
A. His bad habit.  B. His bad teeth.      C. Not smiling.        D. Eating too much sugar.
2. Many people don’t smile because    .
A. they don’t like smiling                    B. they think they are ugly 
C. their teeth are not beautiful               D. they can’t open their mouths
3. What can a dentist do according to the passage?
A. A dentist can tell you how to improve your bad teeth.
B. A dentist can help you to take care of your bad teeth.
C. A dentist can tell you how to brush your teeth.
D. Both A and B.
4. If you want to keep healthy, you had better    .
A. not smile often                         B. laugh all the time 
C. neiter smile nor laugh                  D. smile and even laugh often
5. How many times should a child laugh every day in doctor Kataria’s opinion?
A. Either 300 or 30 times a day.               B. Between 7 and 15 times a day.
C. Around 300 times a day.                     D. Only 30 times a day.