20. Cathy, along with his teacher, (   ) to Guangzhou on business. 

• A、have gone
  
  

• B、has gone
  
  

• C、are going
  
  

• D、have been gone
  
  

16. Of the two mooncakes, which do you like (   ). 

• A、many
  
  

• B、better
  
  

• C、good
  
  

• D、the most
  
  

52 .(    ).