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问题 选择题

某船在静水中的速率为3m/s，要横渡宽为30m的河，河水的流速为5m/s。下列说法中正确的是

A．该船不可能沿垂直于河岸的航线抵达对岸

B．该船渡河的速度最小速度是4m/s

C．该船渡河所用时间至少是10s

D．该船渡河所经位移的大小至少是50m

答案

ACD

由于水速大于船速，则该船不可能沿垂直于河岸的航线抵达对岸，A正确；当船的方向与水流的方向夹角越大，则合速度越小，趋向于2m/s，B错误；当船垂直河岸时渡河时间最短，，C正确；如图所示，当船沿v1方向运动时，位移最小，有：，由几何关系知：，D正确。

单项选择题

下列各句中，没有语病的一句是 ( )

A．人的生活范围、生活阅历总是有限的，阅读可以帮助人们认识世界，了解我们不曾经历、也不可能经历的一些事情。

B．连续几个春节期间的暖冬效应，让我们徜徉在四季不分的温顺的阳光底下，逐渐学会了安逸和本能抗寒能力的退化。

C．刚开始，他们靠从家乡出发时自带的食品、矿泉水、方便面等填肚子，后来因水土不服，很多队员出现拉肚子、发烧等症状。

D．要顺利完成防止经济增长由偏快转为过热、防止价格由结构性上涨演变为明显的通货膨胀，我们还有许多工作要做。
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A Recent Erymology of the Word "Culture"“文化”一词的新词源
Look in an old dictionary—say, a pre-1960 Webster’s—and you’ll likely find a definition of culture (1) looks something like this: "1．The cultivation of soil. 2．The raising, improvement, or development of some plant, animal (2) product. " This use of the word has its roots in the ancient Latin word cultura, "cultivation" or "tending," and (3) entrance into the English language had begun by the year 1430. By the time the Webster’s definition above was (4) , another definition had begun to take precedence over the old Latin denotation; culture was coming to mean "the training, (5) , and refinement of mind, tastes, and manners" (Oxford English Dictionary). The OED traces this definition, which today we associate (6) the phrase "high culture," back as far as 1805; by the middle of the 20th century, it was (7) becoming the word’s primary definition.
However, if you try a more modem source, like the American Heritage English Dictionary, (8) find a primary definition of culture which is substantially different than either of the two given above: "The totality (9) socially transmitted behavior patterns, arts, beliefs, institutions, and all other products of human work and thought. " Why such a (10) , and in such a (relatively) short period of time Well, in the past 40 years, the use of the (11) "culture" has been heavily influenced by the academic fields of sociology and cultural anthropology. These fields have gradually brought (12) was once a minor definition of culture (the last of eight definitions given in the old 1958 Webster’s quoted (13) ) into the mainstream.
It is easy to imagine how the US society which was so focused on "socially transmitted (14) patterns" in the sixties would come to need a word to describe the object of its interest. The civil (15) movement during this era brought everyone’s attention to bear on cultural differences within US society, while the Vietnam War (16) to emphasize the position of the US culture in relation to other world cultures.
Over time, these new uses (17) the word culture have eclipsed its older meanings, those associated with cultivation of the land and the production of (18) . You might say that an aspect of US culture over the past 40 years is its fascination with the (19) of culture itself—a fascination which has brought about many changes in the way we speak and the (20) of words which we commonly use.

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