52＿＿

39.The word"underdog”in Paragraph 1 probably refers to(  )

• A、smart high school students
• B、dogs that are not liked by their owners
• C、students who need help to succeed
• D、poor company workers

18.In the last five years the city＿out rapidly in all directions.

• A、has spread
• B、has been spread
• C、was spread
• D、spread