The author states that during dream sleep, the animal sleeps

• A、without moving
  
  

• B、shallowly
  
  

• C、intermittently
  
  

• D、on its side
  
  

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

 If George took the job in Birmingham, he would have to leave his family at Wyeford.

• A、True
  
  

• B、False
  
  

• C、Not Given