UNIT 07 Human Teeth

　　Teeth are the hardest thing in the human body. They are not made of bone. They are made of enamel, gum and so on. People use teeth when they eat something or tear something. How many teeth do people have? When they are young, they have 20 teeth. And when they get older, they have 32 teeth all together。

　　Select True or False

　　❶ Teeth are the smoothest thing in the body. (T/F)

　　❷ Adults have 20 teeth all together. (T/F)

　　❸ Teeth are used for eating and tearing. (T/F)

　　More to know

　　when

　　when有“在……时”的意思。在疑问句里被用作疑问词，有的时候也

　　在叙述句中作为连词引导句子。

　　··When is your birthday?

　　你的生日是什么时候？

　　··When you are free after school, you can come to my house。

　　你放学后有空的时候，可以到我家来玩。

　　READING COMPREHENSION

　　*Read and circle the best answer。

　　❶ What are teeth made of?

　　a. bone b. steel c. enamel

　　❷ How many teeth do adults have?

　　a. 20 b. 28 c. 32

　　*Complete the sentence with the right answer。

　　❸ The young people usually have teeth。

　　a. 20 b. 24 c. 28

　　❹ Teeth are the thing in the human body。

　　a. softest b. hardest c. largest

　　DESCRIBE THE PICTURE

　　*Circle the correct sentence。

　　❶ A boy and a girl are eating or tearing something。

　　❷ A boy and a girl are writing something。

　　❸ A boy and a girl are riding something。