阅读理解

     Come and look at the photo. It’s an American family. The woman in the middle is Beth White. She is

our teacher. The old woman on her right is her mother. She is Mrs. White. The man on her left is her

father, Mr White. He is an artist. The other young woman is Doris White. She is her sister. Doris White

has two children. They are students. Leo Bush is her son and May Bush is her daughter. May sits

between her grandfather and her father.

     "What are they doing?"

     "The family are having a big dinner on Thanksgiving Day(感恩节)."

1. This is          family photo.

A. an American  

B. an English    

C. a Chinese

2. There are          in Beth White’s family.

A. six people    

B. seven people  

C. five people

3. They are having           .

A. sports  

B. a family meeting  

C. a big dinner on Thanksgiving Day

4. Beth’s family name is           .

A. Smith  

B. White  

C. Bush

5. Leo and May’s father is _________.

A. Mr White    

B. Mr Smith  

C. Mr Bush

环烷烃热裂解时，侧链烷基较烃环（）裂解，长侧链先在侧链中央断裂；环烷脱氢生成芳烃较开环生成烯烃容易。五碳环较六碳环难于裂解。