DNA分子具有多样性的主要原因是（　　）

根据短文内容,  从短文后的选项中选出能填入空白处的最佳选项,  选项中有两项为多余选项。

    Many people think of guys as being carefree when it comes to their appearance. But in fact, a lot of guys spend plenty of time in front of the mirror. ____.

    Body image is a person's opinions and feelings about his or her own body and physical appearance. ____. You appreciate your body for its capabilities and accept its imperfections.

    So, what can you do to develop a positive body image? Here are some ideas:

    Recognize your strengths. Different body types are good for different things. What does your body do well? Maybe your speed, strength, or coordination makes you better than others at a certain sport. That may be basketball, table tennis, mountain biking, dancing, or even running. Or perhaps you have non-sports skills, like drawing, painting, singing, playing a musical instrument, writing, or acting. ____.

    Exercise regularly. Exercise can help you look good and feel good about yourself. Good physiques (体形) don't just happen. ____. A healthy habit can be as simple as exercising 20 minutes to one hour three days a week. Working out can also lift your spirits.

    Respect your body. Practicing good habits — regular showering; taking care of your teeth, hair, and skin; wearing clean clothes, and so on — can help you build a positive body image.

    ____. Your body is just one part of who you are. Your talent for comedy, a quick wit (智慧), and all the other things make you unique. So try not to let small imperfections take over.

A. Be yourself.

B. Just explore talents that you feel good about.

C. Use this as an opportunity to discover what you're good at.

D. They care just as much as girls do about their body image.

E. They take hard work, regular workouts, and a healthy diet.

F. The good news is that self-image and body image can be changed.

G. Having a positive body image means feeling satisfied with the way you look.

I.若将玻璃管缓慢倒转至开口向下,玻璃管中气柱将变成多长?

Ⅱ.接着缓慢升高管内气体温度,温度最高升高到多少摄氏度时,管内水银不能溢出.

请先阅读下面的短文，掌握其大意．然后在每小题所给的A，B，C，D四个选项中，选出可以填入空白处的最佳选项。

    Today some people call Amsterdam the "City of Bicycles" because it is a city which is flat and convenient（方便）for bicycles.

    In the 1960s, a group of cycling fans1an idea . They believed that it would be better for everybody if only bicycles were allowed in the city centre. They were2that this would help to save energy, reduce pollution and provide free public transport. The group painted hundreds of bicycles3and placed them in public places around Amsterdam for people to use.4was allowed to take them and use them for short journeys, whether he was a local or a foreigner, Wherever someone finished a journey, they would5the bike there for someone else to use. The problem was that it didn't work-thieves took all the bicycles6 weeks!

    7,more than thirty years later, the "white bike" is back in town-this time with a computer chip(芯片)to8 its every move! To take a bicycle, you have to put a special card inside. The new "White bike" is not white any more but is an unusual9with bright colours. The bikes are parked at special parking places and people who want to use them have to take them to another place that has enough room.

    There is already less traffic in central Amsterdam, 10 both locals and tourists have been using the white bikes. Thanks to the good ideas of lots of people, like the cycling fans in the 1960s, many people around the world have been enjoying city centre streets without cars for many years.