题干

与大棚种植蔬菜相关的措施及分析中,正确的是(  )

A:施用农家肥,可提高大棚中CO2的浓度

B:加大蔬菜的种植密度,可不断提高蔬菜的产量

C:阴雨天适当提高大棚内温度,可明显增加有机物的积累量

D:用绿色塑料薄膜代替无色塑料薄膜,可提高蔬菜的光合作用速率

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答案(点此获取答案解析)

A

同类题1

阅读下文,完成下列各题。

底线

冯骥才

      ①一个物欲的时代和一个非物欲的时代,人的底线是不同的。社会的底线也在下降。所谓社会底线下降,就是容忍度的放宽。原先看不惯的,现在睁一眼闭一眼了;原先不能接受的,现在不接受也存在了。在商业博弈中,谎话欺骗全成了“智慧”;在社会利益竞争中,损人利己成了普遍的可以获利的现实;诚信有时非但无从兑现,甚至成为一种商业的吆喝或陷阱。在这样的社会生态中,人的底线不知不觉在下降。

      ②可是这底线就像江河的水线,水有一定高度,船好行驶,人好游泳。如果有一天降到了底儿,大家就一起陷在烂泥里。我们连自己是脏是净是谁也不知道了。

      ③所以,人总得有自己做人做事的底线。其实这底线原本是十分清楚的。比如人不能“见利忘义”“卖友求荣”“卖国求荣”“乘人之危”,不能“虐待父母”“以强凌弱”“恩将仇报”“落井投石”,还有“不义之财君莫取”“朋友妻不可欺”等等。

      ④这个古来世人皆知的底线,也是处世为人的标准,似乎已被全线突破了。

      ⑤底线无形地存在于两个地方。一在社会中,一在每个人心里。如果人们都降低自己的底线,社会的底线一定下降。社会失去共同遵守的底线,世道人伦一定败坏;如果人人守住底线,社会便拥有一条美丽的水准线﹣﹣文明。因此说,守住底线,既为了成全社会,也是成全自己。

      ⑥然而,这两个底线又相互影响。关键是在碰到低于你的底线时,你是降下自己的底线,随波速流,还是坚守自己的底线,洁身自好?有人说,在物欲和功利的社会里,这底线是脆弱的。依我看,社会的底线可能是脆弱的,人的底线依旧可以坚强,牢固不破。

      ⑦底线是人的自我基准,道德的基准,处世为人的基准。

      ⑧人的自信是建立在底线上的。没有底线,一定会是一塌糊涂的失败的自我,乃至失败的人生。有底线,起码在“人”的层面上,获得了成功的自我与成功的人生。

(选自2013年6月3日《今晚报》,有删改)

同类题4

阅读下面短文,从短文后面各题所给的四个选项(A、B、C和D中,选出可以填入空白处的最佳选项。

    The cultures of the East and the West really distinguish from each other a lot. This is because the culture systems are two 1 systems on the whole.

    The origin of the eastern culture is mainly from two countries: China and India. Both of the two cultures are gestated(孕育) by 2. In China, the mother river is the Yellow River, 3 the Indian one is the Hindu River. These two cultures have 4 for several thousand years and formed their own styles. Then in Tang Dynasty of China, the Chinese culture 5 went overseas to Japan, 6 into the Japanese society and 7 the Japanese culture nowadays. Though a bit different from the Chinese one, it 8 to the same cultural system.

    When the two mother rivers gave birth to the eastern culture, another famous culture was 9 on the Mesopotamian Plain(米索不达米亚平原): the Mesopotamian Civilization. This civilization later on developed into the cultures of the Ancient Greece and Ancient Rome. And these two are well-known as the 10 of the European culture. 11 the Chinese culture, the European one is also 12 to waters. When the colonists(殖民者) of England 13 in America, their culture went with them over the Atlantic Ocean. So the American culture doesn't 14 from the European one a lot.

    At the same time, the 15 of the language systems adds to the cultural differences. In the East, most languages belong to the pictographic(象形文字的) languages while the Western languages are 16 based on the Latin system, for example, the one I'm using to write this paper.

    Other factors like human race difference counts 17 . However, 18 the far distance and the steep areas between the East and West, the two cultures seldom 19 until recent centuries. 20 they grew up totally in their own ways with almost no interference from the other.