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     森林是人类的朋友,尤其是维护生态环境方面更是功劳卓著。森林涵养水源,保持水土,防止水旱灾害的作用非常大。据专家测算,一片10万亩面积的森林,相当于一个200万立方米的水库,这正如农谚所说的:“山上多栽树,等于修水库、雨多它能吞,雨少它能吐。”森林因这种特殊的“吞吐”功能而被科学家称之为“吞水吐雨器”。它用另一种“能吞能吐”的特殊功能孕育了人类。因为地球在形成之初,大气中的二氧化碳含量很高,氧气很少,气温也高,生物是难以生存的,大约在4亿年以前,海里的先进植物登陆,陆地才产生了森林,森林慢慢将大气中的二氧化碳吸收,同时吐出新鲜氧气,调节气温,这才具备了人类生存的条件,地球上才最终有了人类。所以科学家又称森林是“吞碳吐氧机”。

     森林,是地球生态系统的主体,是大自然的总调度室,是地球的绿色之肺。森林维护地球生态环境的这种“能吞能吐”的特殊功能是其他任何物体都不能取代的。因此,我们必须高度重视植树造林,并且保护好森林-目前,值得我们每个人关注的是地球的绿色之肺在日益萎缩,近200年间,地球上的森林已有三分之一以上被采伐和毁掉。而另一方面,由于地球上的燃烧物增多,二氧化碳的排放量在急剧增加,此消彼长,使得地球生态环境急剧恶化,主要表现为全球气候变暖全球气候变暖,对人类的生产和生活有着巨大的影响,甚至威胁人类生存因为全球气候变暖,水分蒸发加快,改变了气流的循环,使气候变化加剧,从而引发热浪、飓风、暴雨、洪涝及干旱。为了使地球的这个“能吞能吐”的绿色之肺恢复健壮,以改善生态环境,抑制全球变暖,减少水旱等自然灾害。我们应该大力植树造林,使每一座荒山都绿起来。

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    When I was in my twenties, I travelled alone through the UK. In order to 1 locations that the public transportation couldn't get to, I bought a(n)2 car, drove it around for three months and sold it before I returned to Australia. The car cost most of my money, so I lived mainly on3during that trip, it being cheap and filling. In Ireland, my4 was stolen, and it was impossible to get another. So for the rest of the trip I 5out in my car, being too poor to afford bed and breakfast.

    One morning, I 6 in my old Skoda under a twisted tree on a remote lane in the Irish countryside, with no more than a 7 house in sight. I had a terrible desire for a 8 cup of tea and some hot water to make porridge with 9 I would not have to eat the cold leftovers from the previous day.

    My thermos (暖瓶) had gone cold overnight so I knocked on the door of the house. A woman opened it. Hot water? She 10 let me get away with just that! I was invited indoors, seated at the breakfast table with the 11 and given a delicious breakfast, as much as I could eat. I was 12 to eat something more than porridge! I 13 being friends with the whole family.

    That was only one of many acts of 14strangers showed me when I was traveling alone in foreign regions. One London businessman rushing to work, seeing me 15 offered to pull my ridiculously heavy suitcase 16several flights of stairs in the underground. After he'd done so, with a smile and a wave, he 17 into the crowd.

    Kindness gets 18. The other day, I was able to point out a rare parking spot to a young man who had been driving around the railway car park, looking 19 desperate. His grateful smile was all the 20 I needed as I dashed off to catch my train.