[填空题]The filter of the purifier must by cleaned and replaced regularly to work well.

[填空题]The filter of the purifier must by cleaned and replaced regularly to work well.

[填空题]The computer is out of order, you must have it repaired.

[单项选择]Since the two sculptures are （）, one must be a replica of the other.
A. like
B. equal
C. identical
D. equivalent

[填空题]The filter of Ceramic Water Purifier is also painted with colloidal silver because it is used in water purification systems in many aircraft.

[填空题]The filter of the purifier is put in a larger container because communities can make money by producing and selling the containers.

[单项选择]Who cleaned the floor
A. Maria.
B. Kate.
C. The woman.

[填空题]Ceramic Water Purifier has become a household necessity in all the developing countries.

[填空题]Water filtered out of Ceramic Water Purifier is completely safe for drink.

[单项选择]（）unorganized, we cleaned the room
A. Feeling 
B. Felt  
C. We feeling
D. Having felt

[单项选择]Why can’t Tom have the suit cleaned
A. Because he is too busy playing cards.
B. Because he has no work to do.
C. Because he is working at his homework.
D. Because he does not want to.

[单项选择]Theroomisinaterriblemess;it______cleaned.
A. can’t have been
B. shouldn’t have been
C. mustn’t have been
D. will have been waiting

[单项选择]Mr. Johnson worked in a shop which sold, cleaned and repaired hearing aids. One day an old gentleman entered and put one down in front of him without saying a word."What’s the matter with it " Mr. Johnson asked. The man did not answer. Of course Mr. Johnson thought that the man must be deaf and that his hearing aid must be faulty, so he said again, more loudly, "What’s wrong with your hearing aid, sir " Again the man said nothing, so Mr. Johnson shouted his question again as loudly as he could.The man then took a pen and a piece of paper and wrote: "It isn’t necessary to shout when you’re speaking to me. My ears are as good as yours. This hearing aid is my wife’s, not mine. I’ve just had a throat operation, and my problem is not that I can’t hear, but that I can’t speak. "（）
A. To sell hearing aids
B. To buy a hearing aid
C. To have a look
D. To repair a hearing aid