Henry Manley was already deeply in debt. 

• A、True
  
  

• B、False
  
  

• C、Not Given
  
  

The author suggests that, because there are no hiding places in the oceans, whales and dolphins

• A、 sleep only when they are very young
  
  

• B、 cannot afford to sleep very much
  
  

• C、usually dream while awake
  
  

• D、take turns to sleep
  
  

Task 1

16. Paragraph     ①     

17. Paragraph     ②     

18. Paragraph     ③     

19. Paragraph     ④     

20. Paragraph     ⑤     

A. Lightening Causes Puzzles to People

B. Types of Lightning

C. Causes of Lightning

D. Differences Between Thunder and Thunderstorm

E. Frequencies of Thunderstorms Occurring in the World and the U. S.

F. Shock Waves as Thunder