_福州成考网

51.__________,

The passage is mainly about_____．

• A、a group of cold-water-swimming lovers
  

• B、the Polar Bears’life in New York
  

• C、doctors’ideas about cold-water swimming
  

• D、the requirements of the Polar Bear Club

We____have proved great adventurers，but we have done the greatest march ever made in the past ten years．

• A、needn’t
  

• B、may not
  

• C、shouldn’t
  

• D、mustn’t