题干

如图是一些研究电现象和磁现象的实验.下列关于这些实验的叙述正确的是(   )

A:图1中小磁针被铁棒吸引,说明铁棒本身具有磁性

B:图2中小磁针发生偏转,说明电流周围存在磁场

C:图3中条形磁铁静止时A端总是指向北方,说明A端是条形磁铁的南极

D:图4中铁钉B吸引的大头针比A多,说明电磁铁的磁性强弱与电流大小有关

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B

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    Variety is the spice of language. The words listed in this book are not intended to replace those that most people use most of the time. Rather, they are variations on the theme. We tend to use the same old words over and over again, to limit our powers of expression by limiting our vocabulary. ____ but why not enhance your speech and writing by learning to use new ones from time to time ds alternatives?

    How often have you spoken of having an accident? ____ Or why not occasionally describe a situation as aggravated(恶化)instead of worsened.

    I don't mean that you should throw away the Mold words”. ____ English is an especially rich language, and often there are differences between two words that are generally regarded as die same. Thus, a mishap is not merely an accident; it is an unfortunate accident. Because there can be fortunate accidents, like bumping into an old friend you haven't seen for years and whose address you've lost. ____.

    No doubt a good many words in the list will be familiar to you, but do you use them, or do they remain the “property” of others? ____Try to make these words your own, as companions or friendly rivals of the ones you have owned in the past. Let them compete, and make your language all the richer.

A. Just vary them with the “new words”.

B. Many words have more than one meaning.

C. There is nothing wrong with the “old words”.

D. English words are grouped according to their origins.

E. Why not use the alternative mishap once in a while?

F. They are included to introduce variety into your speech and writing.

G. So in using mishap instead of accident, you must be sure of the difference.