--Why are the windows so dirty?
--Because we_________them for a long time.
A. have cleaned B. haven't cleaned C. didn't clean
Mr. Wang often encourages us_______close to nature and enjoy its beauties
A. get B. getting C. to get
--A big fire ______in Dehui, Jilin Province on June 3rd, 2013.
--That's too bad. I think we should try our best to prevent fires.
A. came out B. went out C. broke out
----I think collecting stamps is great fun.
----________We can also learn a lot from it .
A. I agree with you. B. No, I don't think so. C. No, I don't like it.
Nobody will help you________ you help yourself.
A. unless B. because C. though
Once you put your school things___________, you'll find them easily.
A. in danger B.in order C. in detail
