19．Li Ping and Wang Dong are cleaning the _________．

18．_________ is cleaning the blackboard．

17．Tom，Mike and Sun are _________．

16．The students are very _________ in the classroom．

10．A．He usually goes to work by train．

B．He usually' goes to work late．

C．He usually goes to work early．

W：Hi，Peter．What are you doing there?

M：I'm picking some flowers．

W：（11）__________ Do you know?

M：Yes．（12）__________

W：Why?

M：（13）__________He often tells him how to look after them and they often send some to our houses．

W：Oh，I see．（14）__________

M ：To Miss Green．

W：To Miss Green? For what?

M ：（15）__________ Today is her birthday．

W：Really? Let's go together．

C．He finishes his work at 8:00．

9．A．He finishes his work at 5:30．  B．He finishes his work at 5 : 15．

8．A．He goes to work by train．      B．He goes to work by bike．

C．He goes to work by bus．

7．A．It's eight kilometers from his home．

B．It's ten kilometers from his home．

C．It's twenty kilometers from his home．

6．A．He works in a factory．        B．He works in a shop．

C．He works in a company．