London has a population of over 7，000，000．From about the year 1800until World War II，London was the biggest city in the world．But now there are many cities which are much bigger than it．London is famous for many things．Tourists come from all over the world to visit its famous buildings and hear the famous clock，Big Ben．Like many big cities，London has problems with traffic and pollution which stop the city from developing．Over one million people a day use the London underground（地铁），but there are still too many cars on the streets．The air isn't clear，but it is anyhow（不管怎样） cleaner than it was 100years ago．For me，the best things about London are the parks．There are a lot of parks in the city．Five of them are in the city center．But my children's favorite place is Hamleys，the biggest toy shop in the world．

56．When was London the biggest city in the world？___

A．In 1750．

B．In 1850．

C．In 1950．

D．In the 21st century．

57．What's Big Ben in London？___

A．It's a toy shop．

B．It's a park．

C．It'sa clock．

D．It's a museum．

58．How many people use the London underground every day？___

A．Over half of its population．

B．Over three quarters of its population．

C．Over one million．

D．Over 7，000，000．

59．How was the air in London 100yeas ago？___

A．It was much cleaner than it is now．

B．It was the same as it is now．

C．It was the cleanest in the history of London．

D．It was not as clean as it is now．

60．Which of the following statements is true in the passage？___

A．There are not too many cars on the streets．

B．There are 5parks in the city．

C．Many big cities have the problems with traffic and pollution．

D．Children's favorite place is Hamleys，the biggest park in London．