話題介紹

話題：自然。要求通過對本單元核心知識的學(xué)習(xí)，能夠依據(jù)所給的與自然相關(guān)的材料，寫一篇要點和結(jié)構(gòu)完整的內(nèi)容概要（60詞左右）。

建議體裁：說明文、議論文、記敘文等。

注意事項：對文章要點的掌握要全面，不能遺漏重點內(nèi)容；語言通順，邏輯清晰。

題例導(dǎo)學(xué)

題目

閱讀下面短文，根據(jù)其內(nèi)容寫一篇60詞左右的內(nèi)容概要。

When people think of plants， they usually think of gardens， parks， or even jungles （叢林）. One place that does not usually come to mind is the desert. However， some deserts contain many plants that are able to grow and survive under difficult conditions.

Deserts can reach temperatures of 50 degrees or more in the daytime and can also drop below 0 degrees at night. This is a huge temperature difference under which desert plants have to live. Besides the high and low temperatures， all deserts receive very little water in the form of rain; sometimes it doesn’t rain for months. So， how do desert plants get water when there is no rain？

There are three main ways plants survive in the desert. First， some desert plants grow without leaves. Others have developed special ways of storing whatever water they can find， such as growing a waxy （蠟質(zhì)的） leaf covering that helps keep water inside the leaf. These plants can survive for weeks or months on the water collected from just one rainfall.

A second way desert plants survive even in the most difficult conditions is by growing very long roots. These roots spread out and search for any water they can find. Once they find water， the roots suck （吸） up as much as they can and then hold it， only allowing the plant above the ground to have small amounts at a time.

The third way plants survive in the desert is by “sleeping”. Some plants can turn off almost all their processes and just remain inactive， almost as if dead， while they wait for rain. When the rain does come， they quickly drink up every drop they possibly can and burst back into activity.

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思路引導(dǎo)

文章主要介紹的是沙漠不利于植物生長，但有一些植物卻可以在沙漠中存活。概要應(yīng)包含以下要點：

1. 一般植物難以在沙漠中生存，原因：溫差巨大、極度缺水；

2. 有的植物卻能生長，它們的特點和生存方式：特殊的葉子、長根、休眠。

范例展示

Deserts are not suitable places for plants to grow： one reason is the very large difference in temperature， and the other one is the lack of water. However， some plants do grow and survive under desert conditions. That’s because some have special leaves， some grow long roots and some live by remaining inactive until conditions improve.

話題表達

閱讀下面短文，根據(jù)其內(nèi)容寫一篇60詞左右的內(nèi)容概要。

You still need a better reason to plant a tree？

Police aren’t cheap and neither are lawyers， judges， and all the other layers that make up the justice system. But trees and some grass， in comparison， are really cheap， and they prove to be effective in lighting crimes.

Many cities plant vegetation （植物） along roadways to help take in rainwater. After tracking 14 types of crime in nearby areas， Michelle Kondo， a social scientist found that a variety of crimes， such as theft and fights in those areas decreased to 27 percent， an incredible 18 percent fall. Kondo believed planting was able to scare away potential （潛在的） criminals.

Kondo’s study also worked on the connection between grassland care and decrease of the crime in downtown areas. It shows that if you have the time and money to water your plants， you probably live in a neighborhood that sees less crime. Kondo argued that caution （謹(jǐn)慎） of the local people suggested by the organized vegetation helped to frighten away bad guys， by announcing to would-be criminals that there are “eyes on the street’’ that care for their neighborhood and would be more likely to report a crime.

We already know vegetation is beautiful to look at and can help improve mood and health. Now we can add crime-fighting to the list of vegetation’s many benefits. Therefore， are you ready to plant a tree？

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