I felt {#blank#}1{#/blank#}(luck) to have won a place to go on a cultural tour to sites of lost civilizations. We visited Pompeii in Italy and Loulan in China. Pompei {#blank#}2{#/blank#}(found) in the 8^th century BC, then taken{#blank#}3{#/blank#}by the Romans in 89 BC. Later, Pompei was destroyed by a volcano. It erupted and covered Pompei with ash.{#blank#}4{#/blank#} (fortunate), many people were buried alive. The city was forgotten for many years until the 18^th century when a stone with writing on it was discovered by a farmer. People started to dig in the area {#blank#}5{#/blank#}treasure and caused much damage. Thus, in 1860, the area was governed by the government so {#blank#}6{#/blank#}could be preserved and studied.

    Differently, Loulan disappeared under the sand. There were just a few {#blank#}7{#/blank#}(ruin) left. There was {#blank#}8{#/blank#}ancient water system {#blank#}9{#/blank#} (run) through the middle of the city. The desert was once a green with huge trees, but they were cut down,{#blank#}10{#/blank#}resulted in the city being buried by sand.

    They were both important commercial cities about 2,000 years ago. It was a pity that they disappeared for ever.

    Beijing opera or Peking opera is a form of Chinese opera {#blank#}1{#/blank#}(combine) music, vocal performances, dance and so on. It{#blank#}2{#/blank#} (arise) in the late 18th century and became {#blank#}3{#/blank#} (full) developed and recognized by the mid-19th century. The form was extremely popular in {#blank#}4{#/blank#} Qing Dynasty court and has come to be regarded as one of the {#blank#}5{#/blank#} (culture) treasures of China. Major performance troupes (剧团，戏班子）are based in Beijing and Tianjin in the north, and Shanghai in the south. Also {#blank#}6{#/blank#} (preserve) in Taiwan, the art form is still of great importance to people there.

    {#blank#}7{#/blank#} (perform) of Peking opera use the skills of speech, song, dance, and combat in movements that are symbolic and suggestive. Above all else, the skill of performers {#blank#}8{#/blank#} (evaluate) according to the beauty of their movements. The music of Beijing opera can be divided {#blank#}9{#/blank#} the Xipi and Erhuang styles. The repertoire (全部曲目）of Beijing opera includes over 1,400 works, {#blank#}10{#/blank#}characters are based on Chinese history, folklore, and, increasingly, contemporary life.

You Are a Time Traveler

    Time travel has long fascinated people. Traveling to the past or future would allow you to live in exciting periods of history or get a glimpse(一瞥) of {#blank#}1{#/blank#} the future holds. Think about it. If you could travel in time, where would you go? Perhaps you would voyage far ahead of the present day {#blank#}2{#/blank#} (meet)your future self! What about watching an original performance of {#blank#}3{#/blank#} Shakespeare play in Elizabethan England? Or maybe you would pay a visit to {#blank#}4{#/blank#} (you)as a baby.

    Since these ideas are universally appealing to everyone, it is {#blank#}5{#/blank#} (nature)that time travel interests so many writers, filmmakers, and scientists. It has been depicted in a {#blank#}6{#/blank#} (various) of media, such as literature, film, and science reports. But you might be surprised to realize that {#blank#}7{#/blank#} the smallest sense of the term, we are all time travelers. Even as you sit here {#blank#}8{#/blank#} (read)this article, time is racing forward. The future becomes the past as soon as it happens. The present is so fleeting(稍纵即近)! Everything you do quickly {#blank#}9{#/blank#} (become) part of the past, and so it is that we move through time. The famous scientist Albert Einstein, assigned a mathematical formula to this idea, {#blank#}10{#/blank#} is called The Theory of Relativity.

When talking about our bodies, we often forget our skin. Actually, our skin is very important, too. It keeps us{#blank#}1{#/blank#}(inform) of the outside world--{#blank#}2{#/blank#}it is hot or cold, wet or dry.

Try this: pull up the skin from the back of your hand and then let {#blank#}3{#/blank#}go. What happens?

The skin goes back to its first position, which means that skin is elastic (有弹性的).

Our skin seems to be very thin, but it {#blank#}4{#/blank#} (make) up of two layers. The top layer is the one we wash every day. Do you know that this part of skin is dead? However, it is still very important because it serves as{#blank#}5{#/blank#} (protect) against dirt and disease.

Skin has millions of tiny holes called pores(毛孔). Pores allow liquid, especially sweat,{#blank#}6{#/blank#}(pass) through. By{#blank#}7{#/blank#} (sweat), our bodies keep up a normal temperature. When it is very hot, we sweat a lot, but{#blank#}8{#/blank#}(strange) enough, when it is quite cool, we also sweat. On a cool day, our bodies produce {#blank#}9{#/blank#}average of 700 ml of sweat. That is{#blank#}10{#/blank#}(much) than 0.5 kilos.