13、
He came to visit China two days ago.
14、There are twelve studens over there.
4. Sarah can clean the classroom.
5. There are some flowers in the vase.
came to visit China two days ago(两天前).
7. I can speak English well.
8. Tonny had a talk for a long time.
9. They like making the presents（礼物）
10. Jim and Kate often help their grandfathe r on the farm after school.
11、I am good at(擅长) singing and dancing.
12. He wants to be an actor in the future.
play basketball on Sundays.
should take care of the young trees.
15. The girls are singing in the classroom.
16. She has something to eat.
17. Alice came to our home last week(上一周).
18. The little boy is standing on the man's shoulders.
is some fruit juice in the glass.
20. We will visit America next week(下一周).
三，将下列句子变为否定句：
1. He takes some pictures every day.
2. Its cheap enough.
teacher should make the students happy ever y day.
me your library card、please.
5.
She gave her brother some tapes about folk music.
6.
This is the first time we come to Australia .
better make a shopping list first.
are a lot of(量的)lovely animals there.
mother will take me to Beijing for my hol iday next Sunday.
can find many tall trees in the picture o f the park.