A. when; that      
B. that; when  
C. which; when  
D. that; which

A. which        
B. what        
C. in which      
D. of which

[     ]

A. the high of which
B. the highest of which
C. the highest of them
D. which of them

[     ]

A. what
B. which
C. that
D. it

A. when      
B. where      
C. that        
D. which

[     ]

A. that
B. which
C. what
D. where

[     ]

A. all whose homes
B. all of whose homes
C. all their homes
D. all of their homes

[     ]

A. which price
B. the price of which
C. its price
D. the price of whose

A. what
B. that
C. which
D. where

Water is very important to us, without that there would be no life. We couldn't live if we didn't have
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water.Therefore, some people don't turn the tap off at once after using it. Some people don't realize
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they wash them in the shower too long. Some even throw away bottles full in water. As middle
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school students, we should make great efforts to save water. On one hand, every single person's
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save water is significance. On other hand, we can use some water we just used to watering plants.
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We shouldn't leave the tap running for while we brush our tooth.
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