题干

根据短文内容的理解,选择正确答案。   

    Why do plants grow in some places and not in the others? Why does some land have so much growing on it, while other land has almost no plants growing on it at all?

    To grow, plants need several things. One is warmth. In very cold places almost nothing grows. Plants also need water. In very dry parts of the Earth only a few unusual plants can grow. That's why dry deserts everywhere are almost not covered by trees or grass.

    Plants must also have a place in which to put down their roots and grow. They find it difficult to grow on hard land. The town is built on hard land. The plants here have only the soil found between the cracks of the stones to grow in.

    Another thing plants must have before they can grow is food.

What will happen if we try to make things grow on the sandy beach? A few plants, such as beach grass, will grow in sand, but most plants won't. Even if the weather is warm enough and we water the plants each day, many of them will die because the sand on this beach has almost no food for plants.

上一题 下一题 0.0难度 选择题 更新时间:2017-10-06 11:02:23

答案(点此获取答案解析)

同类题3

阅读文言文,回答问题

       十二月,项王至垓下,兵少,食尽,与汉战不胜,入壁;汉军及诸侯兵围之数重。项王夜闻汉军四面皆楚歌,乃大惊曰:“汉皆已得楚乎?是何楚人之多也?”则夜起,饮帐中,悲歌慷慨,泣数行下;左右皆泣,莫能仰视。于是项王乘其骏马,麾下壮士骑从者八百余人,直夜,溃围南出驰走。……汉骑追者数千人,项王自度不得脱,谓其骑曰:“吾起兵至今,八岁矣;身七十余战,未尝败北,遂霸有天下。然今卒困于此,此天之亡我,非战之罪也。今日固决死,愿为诸君快战,必溃围,斩将,刈旗,三胜之,令诸君知天亡我,非战之罪也。”乃分其骑以为四队,四乡。汉军围之数重。项王谓其骑曰:“吾为公取彼一将。”于是项王大呼驰下,汉军皆披靡,遂斩汉一将。是时,郎中骑杨喜追项王,项王瞋目而叱之,喜人马俱惊,辟易数里。项王与其骑会为三处,汉军不知项王所在,乃分军为三,复围之。项王乃驰,复斩汉一都尉,杀数十百人。复聚其骑,亡其两骑耳。乃谓其骑曰:“何如?”骑皆伏曰:“如大王言!”于是项王欲东渡乌江,乌江亭长舣船①待,谓项王曰:“江东虽小,地方千里,众数十万人,亦足王也。愿大王急渡!今独臣有船,汉军至,无以渡。”项王笑曰:“天之亡我,我何渡为!且籍与江东子弟八千人渡江而西,今无一人还;纵江东父兄怜而王我,我何面目见之!纵彼不言,籍独不愧于心乎!”。

                                                                                                                                                                   (选自《资治通鉴·汉纪三》,有删节)

     【注释】①舣(yí)船:停船。