题干

下列各项中,能看做一个生态系统的是(  )

A:一片森林中的所有树木

B:一条小河中的所有植物和动物

C:一个池塘中所有的生物及其中的无机环境

D:一个草地上的阳光、土壤、空气等无机环境

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C

同类题1

阅读下面的文字,完成文后各题

古典诗文中的“扁舟”意象

    “扁舟”是中国古典诗文中最常见的意象之一,承载着中国古代文人淡泊世事、悠然自得的情感,形成了独特的扁舟情结。最早的“扁舟”,并非失意文人所特有,也不具备悲凉或者超脱的韵味。《史记》载:“范蠡既雪会稽之耻,乃乘扁舟浮于江湖。”这里的“扁舟”有隐遁之味,丝毫没有落魄江湖、身处世外的冷寂色彩。

    “扁舟”在古代文人眼里,不仅仅是一只小船,它随着无数文人跌宕坎坷命运的无限延伸,演化为一种绝处逢生的处世观。在儒家提倡的“达则兼济天下,穷则独善其身”的处世准则支配下,古代文人或积极入世,或隐身出世。对于潦倒困厄的人来说,“扁舟”是他们寻求再生的一支苇草。

    “漂泊”是古代知识分子的宿命,也是“扁舟”意象的基本蕴含。古代知识分子或为生计、或为科举、或被放逐,他们背井离乡,天涯漂泊,充满无尽的羁旅乡愁。“扁舟”既是游子漂泊的凭靠,也是其羁旅之愁的寄托。唐代张若虚《春江花月夜》有“谁家今夜扁舟子,何处相思明月楼”的诗句,其中“扁舟”承载着游子无尽的漂泊之苦和思乡之情。杜甫诗中的“扁舟”意象出现得最频繁,表现漂泊思乡的意绪也最强烈。他诗中的“扁舟”意象,承载着诗人生活的苦难和不幸,是古代知识分子追求理想、历尽艰辛的典型写照。

    “扁舟”意象的另一典型蕴含是“自由”。庄子说“饱食而遨游,泛若不系之舟,虚而遨游者也。”这是古代知识分子的人生理想。现实有太多压抑和束缚,他们渴望在“扁舟”中获得精神的自由。苏轼在《前赤壁赋》中借“纵一苇之所如,凌万顷之茫然”这一境象,表达了他面对被贬谪的处境,渴望摆脱精神苦闷,追求自由生活的强烈愿望。张孝祥的《念奴娇•过洞庭》以温和沉浸的心态,表达了与苏轼同样的心境:“玉鉴琼田三万顷,著我扁舟一叶……怡然心会,妙处难与君说。”一条小船附着于万顷碧波之上,在碧波中自由自在地轻漾,充溢着一种皈依自然、天人合一的“宇宙意识”和自由精神。

    隐居是古代知识分子仕途失意的无奈选择及功成身退的理想归宿,是他们最后的精神家园。“扁舟”意象中既蕴含着他们人生的理想与期冀,也蕴含着他们失意的痛苦和灵魂的呼唤。范蠡是古代文人功成身退的典范,但更多人却是因仕途坎坷和无奈而萌生隐居念头,使“扁舟”成为他们仕途失意而隐居的一个意象。苏轼被贬黄州,写下“小舟从此逝,沧海寄余生”的诗句,流露出过隐居生活的念头。李白“人生在世不称意,明朝散发弄扁舟”,表明了他在现实压抑下,欲放浪江湖,过隐逸生活的强烈愿望。

    在常见的“扁舟”意象中,无论是矢志漂泊,还是追求自由,抑或是失意隐居,无不是中国古代文人心路历程的写照,虽蕴含仕途坎坷失意的无奈与消极,但为后世树立了忧国爱民、愤世嫉俗、自由洒脱的光辉典范。

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同类题4

任务型阅读

    Nowadays more and more Chinese parents invest large sums of money to send their children to study abroad. With countless difficulties to face and solve while studying abroad, overseas students should pay attention to the following things.

    Adjust mental attitudes. Experts consider psychological preparation as the most important thing for students studying abroad to consider.____

    Adapt to new learning methods. Chinese students have got accustomed to the domestic exam-oriented education style. They will face changes in the educational system while studying abroad.____

    Be willing to communicate. With no relatives or friends by their sides, the first feeling of Chinese students is loneliness, which makes it especially important to learn to develop relationships with people around them.____Foreigners really like children of this kind and are willing to help them.

    ____Students should ask related teachers to help make plans consistent with their practical condition. Learning plans require students to hold on to the primary direction of their overseas studies and arrange learning content for each course and semester. After the plan is made, they should strictly keep to it.

    Develop self-motivation for learning. Foreign children are used to learning by themselves in or after class.____So studying abroad requires that they should adapt to overseas studies as soon as possible and try their best to learn actively and independently.

A. Students must know they are going abroad to study and not for leisure.

B. Try to find more solutions to adjusting to the open education.

C. Make and stick to learning plans.

D. However, Chinese children are used to teacher-centered education.

E. They should go out of their way to be friendly and strike up conversations.

F. Help children with financial planning.

G. Students should prepare themselves for the attitudes.