『新东方在线托福阅读』为托福考生准备了ETS托福TPO/Official 9 Passage 3阅读练习：The phrase “at random” in the passage is closest in meaning to真题题目及答案解析，TPO/Official 9 Passage 3阅读原文范文音频翻译

托福TPO/Official 9 Passage 3阅读原文The phrase “at random” in the passage is closest in meaning to题目答案及解析-新东方托福官方网校手机版

约五百万年以前，火山群从海底出现，形成了夏威夷群岛，那时的夏威夷群岛与其他大陆截然不同。

When the Hawaiian Islands emerged from the sea as volcanoes, starting about five million years ago, they were far removed from other landmasses.

随后，在烈日与骤雨的交替作用下，光秃秃又粗糙的黑岩表面开始慢慢变软。

Then, as blazing sunshine alternated with drenching rains, the harsh, barren surfaces of the black rocks slowly began to soften.

风将一些很轻的孢子从几千英里以外的远古大陆吹走，孢子随机飘落在光秃秃的山腰上。

Spores light enough to float on the breezes were carried thousands of miles from more ancient lands and deposited at random across the bare mountain flanks.

其中有些孢子落在阴暗高耸的岩石上，在这片土地上生长，发育。

A few of these spores found a toehold on the dark, forbidding rocks and grew and began to work their transformation upon the land.

地衣可能是第一批成功迁徙的植物群。

Lichens were probably the first successful flora.

它们不只是独立生长的植物，每一株地衣都与水藻和真菌结成共生体。

These are not single individual plants; each one is a symbiotic combination of an alga and a fungus.

水藻借助光合作用收集太阳的能量，将其贮藏于有机分子内部。

The algae capture the Sun’s energy by photosynthesis and store it in organic molecules.

真菌吸收岩石的水分和矿物盐，以代谢物的形式将这些物质传递给水藻，为水藻提供养分。

The fungi absorb moisture and mineral salts from the rocks, passing these on in waste products that nourish algae.

很明显，在这些岛屿上建立群体的第一批生物彼此之间是一种共生关系，这是一种依靠两种或多种生物间密切合作的现象，也是岛屿生物群落中非常重要的一项原则。

It is significant that the earliest living things that built communities on these islands are examples of symbiosis, a phenomenon that depends upon the close cooperation of two or more forms of life and a principle that is very important in island communities.

地衣能够加速分解坚硬的岩石表面，将土层变得柔软且含有丰富的矿物质，这些矿物质是熔融岩从地球内部最深处带来的。

Lichens helped to speed the decomposition of the hard rock surfaces, preparing a soft bed of soil that was abundantly supplied with minerals that had been carried in the molten rock from the bowels of Earth.

现在其他种类的生命得以扎根：蕨类植物和苔藓（两种最古老的陆生植物），它们在岩石裂缝中也能生长得很好。

Now, other forms of life could take hold: ferns and mosses (two of the most ancient types of land plants) that flourish even in rock crevices.

这些植物通过孢子繁殖，孢子是极小的受粉细胞，细胞内包含了孕育新生植物的所有遗传信息，但孢子体外没有任何保护层，也不携带提供营养的组织。

These plants propagate by producing spores— tiny fertilized cells that contain all the instructions for making a new plant— but the spores are unprotected by any outer coating and carry no supply of nutrient.

大量的孢子会飘落到母体植物下面的土地上。

Vast numbers of them fall on the ground beneath the mother plants.

有时它们会被水或风带到更远的地方，

Sometimes they are carried farther afield by water or by wind.

但是只有少数落在非常有利位置的孢子才能获得新生，而大多数孢子会落在缺乏营养的土地上。

But only those few spores that settle down in very favorable locations can start new life; the vast majority fall on barren ground.

不过，苔藓和蕨类植物还是因其孢子数量庞大而传到了夏威夷，存活并繁殖开来。

By force of sheer numbers, however, the mosses and ferns reached Hawaii, survived, and multiplied.

有些蕨类植物体型变得巨大，变成了树蕨，现在仍生长在夏威夷森林中。

Some species developed great size, becoming tree ferns that even now grow in the Hawaiian forests.

在蕨类植物进化出来的几百万年后（不过离夏威夷群岛从海底诞生还有很长一段时间）的岁月里，地球上进化出了另一种植物群落：种子植物。

Many millions of years after ferns evolved (but long before the Hawaiian Islands were born from the sea), another kind of flora evolved on Earth: the seed-bearing plants.

种子植物是生物界的一大精彩发明。

This was a wonderful biological invention.

种子有一层表皮包裹着新生植物的遗传物质，表皮中包裹着一种浓缩的营养物质。

The seed has an outer coating that surrounds the genetic material of the new plant, and inside this covering is a concentrated supply of nutrients.

因此，种子与那些裸露的孢子相比，存活的机会大大提升。

Thus, the seed’s chances of survival are greatly enhanced over those of the naked spore.

有一种种子植物叫被子植物，所有开花的植物都是被子植物。

One type of seed-bearing plant, the angiosperm, includes all forms of blooming vegetation.

被子植物的种子被另一层外皮包裹着。

In the angiosperm the seeds are wrapped in an additional layer of covering.

有些外皮是硬的，就像坚果壳一样，可提供额外的保护。

Some of these coats are hard— like the shell of a nut— for extra protection.

还有一些则既柔软又好看，比如桃子或樱桃。

Some are soft and tempting, like a peach or a cherry.

有些被子植物的种子上有薄纱般的羽翼，比如说蒲公英和马利筋的种子。

In some angiosperms the seeds are equipped with gossamer wings, like the dandelion and milkweed seeds.

这些新的特征为种子能够迁徙到新的生活环境提供了更好的途径。

These new characteristics offered better ways for the seeds to move to new habitats.

它们能够随风飘荡，随波逐流，并可保持休眠数月。

They could travel through the air, float in water, and lie dormant for many months.

像椰子那样大粒的、可以漂在水面上的种子会随洋流飘荡，被冲上海岸。

Plants with large, buoyant seeds—like coconuts—drift on ocean currents and are washed up on the shores.

椰子的种子对洋流变动的抗性非常强，它们能够经受住海水长期的浸泡。

Remarkably resistant to the vicissitudes of ocean travel, they can survive prolonged immersion in saltwater.

当它们停靠在温暖的沙滩上，且条件较适宜的时候，种皮便会变软。

When they come to rest on warm beaches and the conditions are favorable, the seed coats soften.

有了内部营养物质的滋养，幼苗会长出根部，在阳光下拓土。

Nourished by their imported supply of nutrients, the young plants push out their roots and establish their place in the sun.

这些植物借助自己的种子更大规模地迁徙到新的地区，甚至会迁徙到夏威夷群岛这样的孤岛上来，夏威夷群岛位于加利福尼亚以西2000英里和日本以东3500英里之处。

By means of these seeds, plants spread more widely to new locations, even to isolated islands like the Hawaiian archipelago, which lies more than 2,000 miles west of California and 3,500 miles east of Japan.

花、草和开花植物的种子长途跋涉来到这些岛屿上。

The seeds of grasses, flowers, and blooming trees made the long trips to these islands.

（草是一种初级的被子植物，他们将种子结在长长的秸秆中，秸秆包裹着种子。）

(Grasses are simple forms of angiosperms that bear their encapsulated seeds on long stalks.)

在惊人的短时间内，许多曾经荒芜的夏威夷群岛上长满了被子植物。

In a surprisingly short time, angiosperms filled many of the land areas on Hawaii that had been bare.

The phrase “at random” in the passage is closest in meaning to

Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.

It can be inferred from paragraph 2 that the fungi in lichens benefit from their symbiotic relationship with algae in what way?

According to paragraph 3, what was the relationship between lichens and ferns in the development of plant life on Hawaii?

Why does the author mention “a nut,” “a peach,” and “a cherry”?

According to paragraph 4, why do seeds have a greater chance of survival than spores do? To receive credit, you must select TWO answer choices.

According to paragraph 5, a major reason that coconuts can establish themselves in distant locations is that their seeds can

According to the passage, which of the following characteristics do spores and seeds have in common?

Look at the four squares  that indicate where the following sentence could be added to the passage. So since the chances of survival for any individual spore are small, the plants have to produce many spores in order to propagate.  Where would the sentence best fit? Click on a square  to add the sentence to the passage.

Directions: An introductory sentence for a brief summary of the passage is provided below. Complete the summary by selecting the THREE answer choices that express the most important ideas in the passage. Some sentences do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage. This question is worth 2 points.

The Arrival of Plant Life in Hawaii When the Hawaiian Islands emerged from the sea as volcanoes, starting about five million years ago, they were far removed from other landmasses. Then, as blazing sunshine alternated with drenching rains, the harsh, barren surfaces of the black rocks slowly began to soften. Winds brought a variety of life-forms. Spores light enough to float on the breezes were carried thousands of miles from more ancient lands and deposited at random across the bare mountain flanks. A few of these spores found a toehold on the dark, forbidding rocks and grew and began to work their transformation upon the land. Lichens were probably the first successful flora. These are not single individual plants; each one is a symbiotic combination of an alga and a fungus. The algae capture the Sun’s energy by photosynthesis and store it in organic molecules. The fungi absorb moisture and mineral salts from the rocks, passing these on in waste products that nourish algae. It is significant that the earliest living things that built communities on these islands are examples of symbiosis, a phenomenon that depends upon the close cooperation of two or more forms of life and a principle that is very important in island communities. Lichens helped to speed the decomposition of the hard rock surfaces, preparing a soft bed of soil that was abundantly supplied with minerals that had been carried in the molten rock from the bowels of Earth. Now, other forms of life could take hold: ferns and mosses (two of the most ancient types of land plants) that flourish even in rock crevices.  These plants propagate by producing spores— tiny fertilized cells that contain all the instructions for making a new plant— but the spores are unprotected by any outer coating and carry no supply of nutrient.  Vast numbers of them fall on the ground beneath the mother plants.  Sometimes they are carried farther afield by water or by wind.  But only those few spores that settle down in very favorable locations can start new life; the vast majority fall on barren ground. By force of sheer numbers, however, the mosses and ferns reached Hawaii, survived, and multiplied. Some species developed great size, becoming tree ferns that even now grow in the Hawaiian forests. Many millions of years after ferns evolved (but long before the Hawaiian Islands were born from the sea), another kind of flora evolved on Earth: the seed-bearing plants. This was a wonderful biological invention. The seed has an outer coating that surrounds the genetic material of the new plant, and inside this covering is a concentrated supply of nutrients. Thus, the seed’s chances of survival are greatly enhanced over those of the naked spore. One type of seed-bearing plant, the angiosperm, includes all forms of blooming vegetation. In the angiosperm the seeds are wrapped in an additional layer of covering. Some of these coats are hard— like the shell of a nut— for extra protection. Some are soft and tempting, like a peach or a cherry. In some angiosperms the seeds are equipped with gossamer wings, like the dandelion and milkweed seeds. These new characteristics offered better ways for the seeds to move to new habitats. They could travel through the air, float in water, and lie dormant for many months. Plants with large, buoyant seeds—like coconuts—drift on ocean currents and are washed up on the shores. Remarkably resistant to the vicissitudes of ocean travel, they can survive prolonged immersion in saltwater. When they come to rest on warm beaches and the conditions are favorable, the seed coats soften. Nourished by their imported supply of nutrients, the young plants push out their roots and establish their place in the sun. By means of these seeds, plants spread more widely to new locations, even to isolated islands like the Hawaiian archipelago, which lies more than 2,000 miles west of California and 3,500 miles east of Japan. The seeds of grasses, flowers, and blooming trees made the long trips to these islands. (Grasses are simple forms of angiosperms that bear their encapsulated seeds on long stalks.) In a surprisingly short time, angiosperms filled many of the land areas on Hawaii that had been bare.