森林是人类文明的摇篮，是最直接影响人类能否生存下去的生态因子_爱下问搜题

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问题单项选择题

森林是人类文明的摇篮，是最直接影响人类能否生存下去的生态因子。森林吸收 C0₂，释放氧气，以此平衡着大气CO₂的比例，据估计，世界上的森林和植物每年产4 000亿吨氧气。森林是造雨者，不但影响降水量，且减缓山坡上的土壤侵蚀。这段话主要支持了这样一种观点，即森林( )。

A．是造雨者

B．吸收CO₂

C．是人类文明的摇篮

D．是最直接影响人类生存的生态因子

答案

参考答案：D

选择题

下列物质属于同系物的是[ ]

A．CH₃CH₂CH₂OH与CH₃CH₂OCH₃

B．与

C．CH₃COOH与HCOOCH₂CH₃

D．CH₃CH₂CH₂CHO与(CH₃)₂CHCH₂CHO

完形填空

完形填空(共20小题；每小题1分，满分20分)
I could have easily gone through life without getting to know one of the most romantic feelings---love for a dog.
For at least ten years my __36 _ had been suggesting that we get a dog. There were several reasons why the idea _37_   . We had noticed that, on our block, couples with no children as a rule 38_ one large or two small dogs. So we got one puppy 39_ we too had no children.
He flew into the house with the 40 of a Formula 1 (一级方程式赛车). In several minutes he ran over all the house, 41 from my shoulder onto the bed, and ended up in the 42 , where my wife washed him with motherly 43 . From that day on, the invisible（看不见的） _44 for the love of the new member of our household began at my home.
He seemed to 45 that at once. Most of the meals that my wife had _ 46   for him with greater care than those for me---he didn’t   47    look at.
Every evening I went out walking with him. I could not know who was walking whom _ 48_ one evening, when, tired from work, I 49   the walk. The dog was very angry and dragged me out.
Last night our dog pulled me by the ear with his teeth, 50 me up in my dream, and dragged me into the kitchen to make me turn off the 51 which had disturbed（干扰）his sleep. I meekly（乖乖地） 52 that I had forgotten to switch off the light, but that was not 53 . He looked at me like a teacher at a pupil who repeatedly makes _ 54   .
Now we finally know who’s the_ 55     at home, and for twenty years we had seriously argued whether it was my wife or I.

A．came up with