London has (21) of about 7,000,000. From about 1800 (22) World War Ⅱ, London was the biggest city in the world, but now there are many cities which are (23) bigger. London is famous (24) many things. Tourists come from all over the world (25) its famous buildings and hear the famous clock, Big Ben. (26) many cities, London has problems with traffic and (27) . Over 1,000,000 people a day use the London underground, but there are still too many cars in the street. The air isn’t clean, but it is cleaner than it (28) 100 years ago. (29) me, the best things about London are the parks. There are five in the city center. But many children’s (30) place is Hamleys, the biggest toy shop in the world!