文档介绍：年全国研究生入学考试英语真题
以下《 xx 年全国研究生入学考试英语真题》由出 guo 考研英语
频道为您精心提供，欢迎大家参考。
Section I Use of English
Directions:
Read the following text. Choose the best word(s) for each
numbered blank and mark [A], [B], [C] or [D] on ANSWER SHEET
1 (10 points)
The human nose is an underrated tool. Humans are often
thought to be insensitive smellers pared with animals, this is
largely because, animals, we stand upright. This meansthat our
noses are to perceiving those smells which float through the
air, the majority of smells which stick to surfaces. In fact, ,
we are extremely sensitive to smells, we do not generally realize it. Our noses are capable of human smells even when these are to far below one part in one million.
Strangely, some people find that they can smell one type of flower but not another, others are sensitive to the smells
of both flowers. This may be because some people do not have the genes necessary to generate smell receptors in the nose. These receptors are the cells which sense smells and send to the brain. However, it has been found that even people
insensitive to a certain smell can suddenly bee sensitive to it when to it often enough.
The explanation for insensitivity to smell seems to be
that the brain finds it to keep all smell receptors working all the time but can new receptors