In 1863 the first underground passenger railway in the world opened in London. It ran for just under seven kilometers and allowed people to avoid terrible {#blank#}1{#/blank#} (crowd) on the roads above as they travelled to and {#blank#}2{#/blank#} work. It took three years to complete and was built using an interesting method. This included digging up the road, {#blank#}3{#/blank#}(lay) the track and then building a strong roof over{#blank#}4{#/blank#} top. When all those had been done, the road surface was replaced.

    Steam engines {#blank#}5{#/blank#}(use) to pull the carriages and it must have been{#blank#}6{#/blank#}(fair) unpleasant for the passsengers, with all the smoke and noise. However, the railway quickly proved to be a great success and within six months, more than 25,000 people were using{#blank#}7{#/blank#}every day.

    Later, engineers {#blank#}8{#/blank#}(manage) to construct railways in a system of deep tunnels (隧道）, which became known as the Tube. This development was only possible with the {#blank#}9{#/blank#}(introduce) of electric-powered engines and lifts. The central London Railway was one of the most {#blank#}10{#/blank#}(success) of these new lines, and was opened in 1900. It had white-painted tunnels and bright red carriages, and proved extremely popular with the public.

    Nowadays, the life of many people in the world is{#blank#}1{#/blank#}(affect) by globle warming. For example, greenhouse gas has a bad effect{#blank#}2{#/blank#}both people and environment. The earth's surface temperature{#blank#}3{#/blank#}(go) up by about 1 degrees centigrade in the past100 years. As a matter of fact, we may feel that we can hardly put up with the extremely hot summer and we can't get accustomed to warm winter. The rise of the earth's surface temperature has made much {#blank#}4{#/blank#}(different) to human health, the existence of creatures {#blank#}5{#/blank#} the balance of ecosystems. There is no doubt that it is human activities that result{#blank#}6{#/blank#}the bad environment. As a {#blank#}7{#/blank#}(consequent), conditions permitting, all countries in the world should try their best {#blank#}8{#/blank#}(improve) our environment. Even if our effect is limited, it will{#blank#}9{#/blank#}(eventual) make a great difference if we keep on{#blank#}10{#/blank#}(work) together to deal with global warming. Without all people's joint efforts, what would our future be like?

    Why is pink or purple a color for girls and blue or brown for boys?

The answer depends largely {#blank#}1{#/blank#}cultural values as well as personal experiences. To the Egyptians, green was a color {#blank#}2{#/blank#} represented the hope and joy of spring, while for Muslims, it means heaven. Red is a symbol of good luck in many cultures. During the Spring Festival in China, children {#blank#}3{#/blank#} (give) money in a red envelope to bring good fortune in the New Year. For many nations, blue is a symbol of protection and religious beliefs. Greek people often wear a blue necklace hoping to protect{#blank#}4{#/blank#}against evils（灾祸）.

People's {#blank#}5{#/blank#} (choose) of colors is also influenced by their bodies' reactions toward them. Green is said to be {#blank#}6{#/blank#} most restful color. It has the ability to reduce pain and relax people both mentally{#blank#}7{#/blank#}physically. People {#blank#}8{#/blank#}(work) in green environment have been found to have fewer stomach aches.

Red can cause a person's blood pressure to rise and increase people's appetites（食欲）. Many decorators will include different shades of red in the restaurant. And many commercial websites will have a red "Buy Now" button because red is a color that {#blank#}9{#/blank#}(easy) catches a person's eye.

Blue is another calming color. Unlike red, blue is believed to cause people to lose appetite. So {#blank#}10{#/blank#} you want to eat less, some suggest that eating from blue plates can help.