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				38．  the safety of gas, the government has checked the city’s gas supply system thoroughly.    A．To ensure   B．Ensuring    C．Having ensured.      D．To have ensured			【查看更多】
			


		
           
          


		
          
		
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            ____the safety of gas, the government has checked the city’s gas supply system thoroughly. 
            
          A. To ensure           B. Ensuring        C. Having ensured        D. To have ensured
          

			
          
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             the safety of gas, the government has checked the city’s gas supply
system thoroughly.
          


          
 
          
  
  
          A．To ensure
          
            		
  
  
          B．Ensuring
          
            		
  
  
          C．Having ensured.
          
            		
  
  
          D．To have ensured
          
            		
 
          

          


           
          

			
          
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          ________ the safety of gas, the government has checked the city’s gas supply system thoroughly．

          1. A.
            To ensure
          2. B.
            Ensuring
          3. C.
            Having ensured
          4. D.
            To have ensured
          

			
          
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          _______the safety of gas, the government has checked the city's gas supply system thoroughly. 
          

          [     ]
          A. To ensure 
          B. Ensuring 
          C. Having ensured. 
          D. To have ensured 
          

			
          
				查看答案和解析>>
			
          
		
          
				
          
									
                 the safety of gas, the government has checked the city's gas supply system thoroughly.
          

          [     ]
          A. To ensure       
          B. Ensuring      
          C. Having ensured       
          D. To have ensured
          

			
          
				查看答案和解析>>
			
          
		
          
						
          
				
          
	
          
	
          
		
          


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