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, theharsh,barrensurfaces of the black rocks slowly began to soften. Winds brought avarietyof life-forms.

Spores light enough tofloaton the breezes were carried thousands of miles from moreancientlands and depositedatrandomacrossthebaremountain flanks. A few of these spores found a toehold on the dark, forbidding rocks and grew and began to work theirtransformationupon the land. Lichens were probably the first successfulflora. These are not singleindividualplants; each one is a symbioticcombinationof analgaand afungus. Thealgaecapturethe sun's energy byphotosynthesisand store it inorganicmolecules. Thefungiabsorbmoistureandmineralsalts from the rocks, passing these on inwasteproducts thatnourishalgae. It issignificantthat the earliest living thing that built communities on these islands are examples of symbiosis, aphenomenonthat depends upon the closecooperationof two or more forms of life and aprinciplethat is very important in island communities.

Lichens helped to speed thedecompositionof the hard rock surfaces, preparing a soft bed of soil that was abundantly supplied with minerals that had been carried in themoltenrock from the bowels of Earth. Now, other forms of life could take hold: ferns and mosses (two of the mostancienttypes of land plants) thatflourisheven in rock crevices. These plantspropagateby producing spores–tinyfertilizedcells thatcontainall the instructions for making a new plant–but thesporeare unprotected by any outercoatingand carry nosupplyofnutrient. Vastnumbers of them fall on the groundbeneaththe mother plants. Sometimes they are carried fartherafieldby water or by wind. But only those few spores thatsettledown in veryfavorablelocations can start new life; thevastmajorityfall onbarrenground. By force ofsheernumbers, however, the mosses and ferns reached Hawaii, survived, and multiplied. Somespeciesdeveloped 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 offloraevolved on Earth: the seed-bearing plants. This was a wonderful biological invention. The seed has an outercoatingthat surrounds thegeneticmaterialof the new plant, and inside this covering is a concentratedsupplyof nutrients. Thus the seed’s chances ofsurvivalare greatly enhanced over those of thenakedspore. One type of seed-bearing plant, theangiosperm, includes all forms of bloomingvegetation. In theangiospermthe seeds are wrapped in anadditionallayerof covering. Some of these coats are hard–like theshellof a nut–forextraprotection. Some are soft and tempting, like a peach or a cherry. In some angiosperms the seeds are equipped with gossamer wings, like thedandelionand milkweed seeds. These new characteristics offered better ways for the seed to move to new habitats. They could travelthroughthe air,floatin water, and liedormantfor many months.

Plants with large,buoyantseeds—like coconuts—drifton ocean currents and are washed up on the shores. Remarkablyresistantto the vicissitudes of ocean travel, they cansurviveprolongedimmersion in saltwater when they come to rest on warm beaches and the conditions arefavorable, the seed coats soften. Nourished by their importedsupplyof nutrients, the young plants push out their roots andestablishtheir place in the sun.

By means of these seeds, plantsspreadmore widely to new locations, even toisolatedislands like the Hawaiianarchipelago, 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 thatbeartheir encapsulated seeds on long stalks.) In a surprisingly short time, angiosperms filled many of the land areas on Hawaii that had beenbare.

Questions:
question_stem: The phrase “at random” in the passage is closest in meaning to
choices: tag: A
text: finally

tag: B
text: over a long period of time

tag: C
text: successfully

tag: D
text: without a definite pattern
answer_key: D
explanation: at random: 随机。A 是最终；B 是经过很长一段时间；C 是成功地；D 是没有特定的模式。所以 D 的 without definite pattern 正确。对应原文：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.原句说：spore 能够被风搬运到很远的地方，并且怎么样散落到 mountain flank，风吹的东西明显不可能很确定。ABC 都没有体现出风搬运的特点，错。

question_stem: It can be inferred from paragraph 2 that the fungi in lichens benefit from their symbiotic relationship with algae in what way?
choices: tag: A
text: The algae help the fungi meet some of their energy needs.

tag: B
text: The algae protect the fungi from the Sun's radiation.

tag: C
text: The algae provide the fungi with greater space for absorbing water.

tag: D
text: The fungi produce less waste in the presence of algae.
answer_key: A
explanation: A 以 lichen, fungus 和 algae 做关键词定位至第三句以后，说 algae 捕获太阳能并储存，而 fungi 从土壤中吸收矿物质，滋养 algae。问的是 fungi 如何受益，所以前半句是答案，A 正确。B 虽然提到 sun，但不是保护，注意不要错选；C 和 D 都没说。

question_stem: 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.
choices: tag: A
text: Some of the earliest important examples of symbiosis—the close cooperation of two or more living things—occur in island communities.

tag: B
text: Symbiosis—the close cooperation of pairs or small groups of living organisms—is especially important in these island environments.

tag: C
text: The first organisms on these islands worked together closely in a relationship known as symbiosis, which is particularly important on islands.

tag: D
text: It is significant to note that organisms in the beginning stages of the development of island life cannot survive without close cooperation.
answer_key: C
explanation: C, 原文说岛上最早的生物是能够 symbiosis 的，然后解释了 symbiosis。A 的 occur on island community 是概念偷换，原文是用来修饰 living thing 的，没有 occur 这一层主要的意思，错；原文说生物能 symbiosis，然后才说 symbiosis 很重要，B 遗漏信息，没提到最早的生物，错；C 正确；D 完全改变了原文的结构，错。

question_stem: The word “abundantly” in the passage is closest in meaning to
choices: tag: A
text: occasionally

tag: B
text: plentifully

tag: C
text: usefully

tag: D
text: fortunately
answer_key: B
explanation: abundantly: 丰富地，大量地。A 是偶尔的；B 是大量地，丰富地；C 是有用地；D 是幸运地。所以 B 的 plentifully 正确。对应原文: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.原句说 lichens 加快了岩石的分解，怎么样提供了岩石中的 mineral，岩石分解了，岩石中的矿物会分散到土壤中，肯定就多了。A 的 occasionally 说反；C 和 D 完全不靠谱。

question_stem: The word “propagate” in the passage is closest in meaning to
choices: tag: A
text: multiply

tag: B
text: emerge

tag: C
text: live

tag: D
text: evolve
answer_key: A
explanation: propagate: 繁殖，传播。A 是繁殖，增加；B 是浮现；C 是生存；D 是进化。所以 A 的 multiply 正确。对应原文:These plants propagate by producing spores–tiny fertilized cells that contain all the instructions for making a new plant–but the spore are unprotected by any outer coating and carry no supply of nutrient.原句说这些植物通过产生小的 spore 来干嘛，对 spore 的解释是小的细胞，包含 making a new plant 的所有必要信息，从 making a new plant 看出是繁殖的意思，所以正确答案是 A。

question_stem: According to paragraph 3, what was the relationship between lichens and ferns in the development of plant life on Hawaii?
choices: tag: A
text: Ferns were able to grow because lichens created suitable soil.

tag: B
text: The decomposition of ferns produced minerals that were used by lichens.

tag: C
text: Lichens and ferns competed to grow in the same rocky environments.

tag: D
text: Lichens and ferns were typically found together in volcanic areas.
answer_key: A
explanation: A 以 lichen 和 fern 做关键词定位至前两句，说 lichen 分解了岩石，准备了富含矿物质的土壤，接着其他的植物就来了，然后就出现了 fern，所以 lichen 对 fern 的作用是提供适合生长的土壤，A 正确。B 错，原文说 decomposition 的不是 fern，是岩石；C 和 D 都没说。

question_stem: The word “This” in the passage refers to
choices: tag: A
text: the spread of ferns and mosses in Hawaii

tag: B
text: the creation of the Hawaiian Islands

tag: C
text: the evolution of ferns

tag: D
text: the development of plants that produce seeds
answer_key: D
explanation: D this 指代之前的整个句子，就近原则看后半句，说另外一个 flora 在地球上进化出来，冒号之后就是那个 flora，即：seed-bearing flower，所以后面的那个 this 应该指的是这个 flora 的进化，从 this 所在的句子的表语知道，this 是一个生物的 invention，就更能肯定答案是 D。

question_stem: Why does the author mention “a nut”, “a peach”, and “a cherry”?
choices: tag: A
text: To indicate that some seeds are less likely to survive than others

tag: B
text: To point out that many angiosperms can be eaten

tag: C
text: To provide examples of blooming plants

tag: D
text: To illustrate the variety of coverings among angiosperm seeds
answer_key: D
explanation: 功能目的题，这几个词所在的句子本身就是个例子，所以往前看，前一句说 angiosperm 的种子外面有一层种皮，紧接着就说有的外皮是硬的，比如 blabla，有的外皮是软的，比如 blabla，也就是为了说外皮可以分为不同类别才举的例子，所以 D 正确，其他的都没说。

question_stem: The word “dormant” in the passage is closest in meaning to
choices: tag: A
text: hidden

tag: B
text: inactive

tag: C
text: underground

tag: D
text: preserved
answer_key: B
explanation: dormant: 休眠的，睡眠的，静止的，潜伏的。A 是隐藏的；B 是不活动的，闲置的；C 是地下的；D 是保存的。所以 B 的 inactive 正确。对应原文：These new characteristics offered better ways for the seed to move to new habitats. They could travel through the air, float in water, and lie dormant for many months. 原句的前一句说这些特点使得种子更容易 move 到新的地点去，接着说能够 travel through air，float in water，既然是移到新地点，在到达新地点之前种子是不能发芽的，所以应该不活跃。hidden 看不见明显不对，因为前面不管是在空气还是在水里都能看见；在地下的话种子就没法动了，所以 underground 不对；preserved 保存完全不靠谱。

question_stem: According to paragraph 5, a major reason that coconuts can establish themselves in distant locations is that their seeds can
choices: tag: A
text: survive long exposure to heat on island beaches

tag: B
text: float and survive for long periods in ocean water

tag: C
text: use saltwater for maintenance and growth

tag: D
text: maintain hard, protective coats even after growing roots
answer_key: B
explanation: B : 以 coconut 做关键词定位至第一句，但这句话明显与问题无关，只能往下看，而且 distant location 与原文第二句的 ocean travel 同义重合。说它们能够生活在长期的 immersion 下，正确答案 B，注意 C 虽然提到了 saltwater，但 maintenance 和 growth 都没说。

question_stem: According to the passage, which of the following characteristics do spores and seeds have in common?
choices: tag: A
text: They may be surrounded by several layers of covering.

tag: B
text: They are produced by flowering plants.

tag: C
text: They may be spread by wind.

tag: D
text: They are able to grow in barren soils.
answer_key: C
explanation: C，考全文的题，关注各段的首末句。第二段的第一句说 spore 能够被风吹走，第四段的最后一句说 seed 能够在空气中散播，所以两者的共同点是 C。A 和 B 是只有 seed 才有的，spore 没有；D 是只有 spore 才有的，seed 没有。