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The definition of the standard kilogram is almost entirely wrong. Getting that definition right is a challenge that has tried the patience and intelligence of scientists for decades.
Scientists use just seven basic units to define all the other quantities we use — quantities such as speed or electric power. All of those basic units except the kilogram are themselves defined according to natural properties（屬性）that are beyond human control.
For example, the standard second (time) is defined as a specific number of vibration（振動）of a type of radiation sent out by atoms of a special metal. The standard metre (length), in turn, is defined as the length of the path light travels under certain conditions.
Not so the kilogram. This orphan of the basic unit family is simply the mass of a small platinum-iridium alloy cylinder（鉑—銥合金筒）locked away in a container maintained by the International Bureau of Weights & Measures in Sevres, France, near Paris. Official bodies around the world have copies of the cylinder.
Embarrassingly, the last time the copies were brought to Sevres for a checkup in the 1980s, officials found that some copies had gained about 20 parts per billion in weight compared to the master cylinder since the previous checkup in the 1940s. This implies that the master cylinder itself may be an inconstant standard.
Several efforts in several different countries are under way to redefine the kilogram according to basic physical quantities such as counting the actual number of atoms of a specific substance in a kilogram or the electromagnetic（電磁的）force that balances a kilogram mass against gravity. A project of the latter type at the laboratories in Gaithersburg, Md., hopes eventually to define mass by means of electrical units.
So far, none of these redefinition projects has borne fruit. They require the very accuracy of measurement and control of experimental conditions. The slightest influence — even a tiny change in weather — can ruin results. You’ve got to hand it to scientists who are willing to devote many years to such painstaking — but extremely important — research.
小題1: Compared with other basic units, the kilogram is ____.
A．as accurate as other basic units
B．not universally accepted in the world
C．not defined according to natural properties
D．defined in the same way as other basic units
小題2:The author introduced the examination of copies of a platinum-iridium alloy cylinder in the 1980s to indicate that ____.
A．the causes of weight changes had been found
B．such kind of checks had been carried out regularly
C．the changes in weight challenged the definition of the kilogram
D．the consequences of such changes were great in research
小題3: According to the passage, to define the weight of mass by means of electrical units ____.
A．is the only way to redefine the kilogram scientifically
B．has been accepted as the only possible redefinition project
C．is not as complicated as people understand
D．has been considered by some scientists as a better approach
小題4: Which of the following cannot be concluded from the passage?
A．Scientists will achieve success in redefining the kilogram in the near future
B．Some scientists are trying to redefine the kilogram according to basic physical quantities.
C．The redefining of the standard kilogram is quite complicated and can be affected by a number of factors.
D．A number of experiments are being carried out to redefine the kilogram.
小題1:C小題1:C小題1:D小題1:A
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People who show confidence really seem to have it made. They seize more rewarding careers, keep good relationships, and just seem to do everything with more styles than the rest of us.
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In order to get a true sense of Indian Creek School, you should come for an Admission Tour, which includes a personal meeting focusing on your child, a tour of the building and the classrooms, and a discussion of the curriculum(課程).
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科目：高中英語 來源：不詳 題型：閱讀理解

Parents are a child’s first teachers. But some parents never learned from good examples. In New York City, a nonprofit agency called Covenant House tries to help homeless young mothers become good parents.
The twelve or so teenagers who live at the shelter attend parenting classes four days a week. The class is called Mommy and Me. Teacher Delores Clemens is a mother of five and a grandmother. She teaches basic skills, like how to give a baby a bath and how to dress a baby depending on the season.
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In class, with her baby son is Natasha. She lived on the streets. She is glad not only for the warmth and shelter of Covenant House. As she told reporter Adam Phillips, she is also glad for the help they offer in seeking a more secure life.
The World Health Organization says the United States has forty-one births for every one thousand girls age fifteen to nineteen. That is higher than other developed countries, as well as some developing ones. By comparison, northern neighbor Canada has fourteen births and southern neighbor Mexico has eighty-two.
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A．Parents who are a child’s first teachers.
B．A class where teens learn mothering and are mothered.
C．A nonprofit agency that offers a more secure life.
D．A kind teacher who help homeless young mothers.
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A．help homeless young mothers become good parents
B．provide homeless young mothers with a warm shelter
C．help mothers in New York be good parents
D．teach some parents how to love their children
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A．She has a mother of five and a grandmother.
B．She thinks a crying baby should be picked up and hugged.
C．She teaches advanced skills on how to be good mothers.
D．She is very glad for the warmth and shelter of Covenant House.
小題4: According to the World Health Organization, which country has the highest births for girls age fifteen to nineteen?
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科目：高中英語 來源：不詳 題型：閱讀理解

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小題1:All the following statements are true about the phrase “ordinary items” in Paragraph 2 EXCEPT __________.
A．ordinary items never say “New and Improved” or “All Natural”
B．ordinary products are usually cheaper than famous brands
C．producers spend less money on packaging of ordinary items
D．the quality of ordinary items is usually as good as that of famous brands
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A．They are believable.B．They are attractive.
C．They are full of misinformation.D．They are helpful to consumers.
小題3:One of the author’s suggestions to consumers is __________.
A．to make use of ads
B．not to buy items with words like “New and Improved” or “All Natural”
C．to buy high quality items such as famous brands after lunch
D．to buy any ordinary items instead of famous brands
小題4:The author implies that __________.
A．going into the supermarket hungry, you may buy more than you plan to
B．the quality of ordinary items is usually high and the prices are relatively low
C．discount clothing stores are good places to go to
D．ads sometimes don’t tell the truth

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