题干

盒中有标号分别为0,1,2,3的球各一个,这些球除标号外均相同.从盒中依次摸取两个球(每次一球,摸出后不放回),记为一次游戏.规定:摸出的两个球上的标号之和等于5为一等奖,等于4为二等奖,等于其它为三等奖.
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同类题4

阅读理解

    As is often the case, when your teacher asks a question, there is only one correct answer. But there is one question that has millions of current answers. That question is "What's your name?" Everyone gives a different answer, but everyone is correct.

    Have you ever thought about people's names? Where do they come from? What do they mean?

    People's first names, or given names, are chosen by their parents. Sometimes the name of a grandparent or other member of the family is used. Some parents choose the name of a well-known person. A boy could be named George Washington Smith; a girl could be named Helen Keller Jones.

    Some people give their children names that mean good things. Clara means "bright"; Beatrice means "one who gives happiness"; Donald means "world ruler"; Leonard means “as brave as a lion”.

    The earliest last names, or surnames, were taken from place names. A family with the name Brook or Brooks probably lived near brook(小溪); someone who was called Longstreet probably lived on a long, paved road. The Greenwood family lived in or near a leafy forest.

    Other early surnames came from people's occupations. The most common occupational name is Smith, which means a person who makes things with iron or other metals. In the past, smiths were very important workers in every town and village. Some other occupational names are: Carter — a person who owned or drove a cart; Potter — a person who made pots and pans.

    The ancestors of the Baker family probably baked bread for their neighbors in their native village. The Carpenter's great-great-great-grandfather probably built houses and furniture.

    Sometimes people were known for the color of their hair or skin, or their size, or their special abilities. When there were two men who were named John in the same village, the John with the gray hair probably became John Gray. Or the John was very tall could call himself John Tallman. John Fish was probably an excellent swimmer and John Lightfoot was probably a fast runner or a good dancer.

    Some family names were made by adding something to the father's name. English-speaking people added –s or –son. The Johnsons are descendants of John; the Roberts family's ancestor was Robert. Irish and Scottish people added Mac or Mc or O. Perhaps all of the MacDonnell's and the McDonnell's and the O'Donnell's are descendants of the same Donnell.

同类题5

A) 请认真阅读下列短文,并根据所读内容填入一个最恰当的单词。

注意:每个空格只填1个单词。

    More and more British people are deciding not to eat meat and animal products. As a result, vegetarianism(素食主义) is increasing in the UK. According to the Vegetarian Society, 2000 people are giving up meat and “going veggie(素食)” in Britain every week. There's even a National Vegetarian Week organized every year to encourage people to try a meat-free lifestyle.

Vegetarians and vegans

    Vegetarians are people who don't eat or use any animal products. They are becoming more and more common in the UK culture. A recent survey showed that 3 million people (5.7 percent of the country's population) were vegetarians.

A healthy diet

    So why are British people cutting out meat? Many are unhappy about the poor treatment of animals and the effects of meat and fish production on the environment. Worries about food safety, for example mad cow disease, also play a part. Others choose to change their eating habits to get healthier. According to the Vegetarian Society, a meat-free diet could help prevent the certain cancers, as well as heart disease and high blood pressure(压力).

Organic(有机的) farming

    Another rising trend appears in the UK's food production. They want their food to be organically produced. Organic farmers use very few or no chemicals. Organic meat is produced without the use of drugs. Organically farmed animals also have more living space and more good food. According to the Soil Association, three out of every four UK families now buy some type of organic food.

Vegetarianism is becoming____ in the UK

Vegetarianism is increasing in the UK ____ more and more British people are choosing to live a meat-free style.

The government ____ a National Vegetarian Week every year to encourage people to stop eating meat.

Vegetarians and vegans

Vegetarians don't eat or use any ____ products.

It is reported that the ____ of vegetarians in the UK is about 3 million .

A healthy diet

Three____ for cutting out meat

Some people think the production of meat and fish may harm both the animals themselves and the____

Some people are____ about food safety. They don't think the meat they eat are safe enough.

A meat-free diet could help reduce the ____ of the certain cancers, as well as heart disease and high blood pressure.

Organic farming

Organic farmers use very few or no chemicals. Organic meat is produced without ____ drugs.

At present, about 75% of UK families buy some type of organic food.