用方框内所给单词的适当形式填空。每空格限填一词，每词限用一次。

1. Liu Xiang is the best           in China now.

2. Robert likes music. He wants to be a          

3. Rick is twelve. Today is his         birthday.

4. This is my cousin, Bob.           mother is my aunt.

5. Many          are here. You can take the number 7 bus to the hotel.

6. Sandra often               her teeth at seven o'clock in the morning.

7. My father and mother               teachers. They teach(教) the students math.