题干

佳佳同学在做“测量小灯泡电功率”的实验时,设计并连接了如图甲、乙所示电路,小灯泡上标有“2.5 V”字样.

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同类题3

   Zhalong is a nature reserve in Heilongjiang in north-east China. It is one of the world’s most important wetlands. The reserve covers an area of 210,000 hectares. The area provides food and shelter for wildlife. It is an ideal home for different kinds of plants, fish and birds.
   Many birds live comfortably in Zhalong Nature Reserve all year round, while some only stay there for a short time. There are many fish in the wetlands, and the birds can easily catch them for food. Zhalong has long been called “the home of the crane”. There are 15 crane species (物种) in the world. 8 of them are in China and there are 6 species in Zhalong area. It is an important living area for the rare red-crowned cranes. There are not many red-crowned cranes in the world. Every spring and summer, red-crowned cranes lay and hatch (孵化) their eggs in Zhalong.
   Some people want to change the wetlands to make more space for farms and buildings. This means there will be less and less space for wildlife. More and more birds are in danger because they do not have enough living space. Many of them died. The Chinese government wants to protect these endangered birds, and they can be safe in Zhalong.
   Every year, a lot of tourists go to Zhalong to watch birds. This year, members of our Bird-watching Club are going to study the different kinds of birds in Zhalong and the changes in their numbers. The study begins next month.
   We _______ once a year. We are now inviting secondary school students to help. We need more people to help us count and do something to help the birds.
   Many people do not understand the importance of the wetlands. We hope this information will help them understand and make them actively take action to protect wildlife.


同类题5

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。

How to Enjoy Life As a Teen

    The "best years of your life"? Maybe not, but you can learn to make the most of your high school days.

    Learn to appreciate small things. Whether it's having a computer, having friends, having a good supply of food, a bed to sleep on, family that loves you, having a decent education or simply being born in this world, value it. ____ Be happy, and life will reward you. Remember that these are the last few years you will be able to enjoy yourself without having to worry about the responsibility of an adult, but make sure you prepare yourself for when you do become one. When you actually become an adult, you'll learn to love that responsibility and you probably never want to go back.

    Choose your friends wisely. Unlike what many articles state, you don't have to be popular and have a gazillion friends to be happy. ____ Try to have friends that like you who you are, not just because you are wearing a certain brand of shoes or something like that. These are people who shop at the same store as you; not someone who will sympathize with you when your dog dies.

    Keep your grades up. ____ This also sets you up to get into a college you want to go to, which in turn prepares you for a career you will enjoy, improving your quality of life in the future. You'll get cheap car insurance as well if you have at least a B or A average.

    ____ Participating in clubs, activities, and sports increases your chances of meeting new friends. While you only need 4 or 5 close friends, that doesn't mean you shouldn't try to meet new people. Participating gives you something to do instead of sitting bored at home and wallowing in self-pity.

    Work at a job you can enjoy. Working is a great way co gain experience and to meet other people. ____ This will look great on your resume. If you can't find work, especially in this hard economic time, volunteer or make your own job.

A. Be sociable.

B. Remember the point of life is for you to enjoy it.

C. Find a hobby that is meaningful or practical.

D. In fact, many of the "friends" you have when you are popular are not true friends.

E. When you do get out of college, interviewing companies will look at your previous work experience.

F. Even though you want to enjoy your teen life as best as possible, don't idle away your time in school.

G. There is nothing more satisfying than seeing your hard work pay off in the form of A's and B's (but mainly A's).