s.first， with the development of industry， more and more factories have been built and have sent out smoke and
poisonous gases.thus the air
is polluted. the
increasing number of cars adds to the air pollution. second， farmers use chemical fertilizers
to increase production and insecticide to kill insects. when rain flows with these
poisonous chemicals to rivers， water is polluted. a third formof pollution， noise， is becoming
more and more serious. very loud noises can make people sick， and even drive them mad.
____________________________________________________________________________________________________________________________
（2）
there are three important findings from studies concerned with
notetaking. first，notetaking does not interfere with
listening and comprehension； in fact， it helps you listen. second， students who study their lecture notes remember one and a half
times more after six weeks than students who do not review. third， students who take no notes， or do not study their notes， forget approximately 80percent of
the lecture by the end of two weeks.from these findings we can conclude that students who take enough
notes and then study them， both directly after the lecture and several additional times before
an examination， stand a good
chance of remembering between90 and 100％ of the material！_______________________________________
____________________________________________________________________________________________________________________________
第六单元 如何写好一个段落（1）
6.1段落的特征
一个好的段落应该具有以下三个特征：1）完整性（completeness）； 2）统一性（unity）； 3）连贯性（coherence）。
6.2完整性
段落的完整性指的是段落得以充分展开。作者一俟写好主题句，就应该用细节进行推展，细节越充足越好。例如，你认为“riding motorcycles is dangerous”，你就应该用你所知道的事实证明这一观点是正确的。你可以使用数字（statistics），列举例子（example），进行描绘（descriptions）等等。
示范段落6-1
ever since the time of the greeks， drama has played an important role in man's lives. the greek tragedies and come dies
were a central part of the citizens' lives in ancient greece. during the middle ages， bible stories were acted out in
churches，and wandering
companies of players performed in the streets. in modern times， drama is brought directly into people's homes through the magic of
television.
6.3示范段落分析
主题句： ever since the time of the
greeks， drama has
played animportant role in man's lives.
细节：1. ancient greece
2. the middle
ages
3. modern times
作者根据各个不同历史时期提供细节，举例说明戏剧的重要性。
6.4 统一性
一个好的段落应该具有统一性。统一性就是一个中心思想统领整个段落。每个细节都应支持主题句，不应有无关的细节。为了支持主题，要尽可能多地提供细节，但又要避免滥用细节。
读下面段落，然后找出毛病。
1 innovations， whether practical or aesthetic， are often resisted by the general
population.2 when the
early experiments in the field of aviation began their work， there were many who said，“if god had wanted man to fly， he would have given him wings.3the wright brothers made the first
powered flights in a heavier-than-air craft in 1903 at kitty hawk， north carolina.4even today there are many who
strongly object to modern art and music as being nothing more than “splashes of paint and honking horns.”5the painter picasso's well-known
masterpiece “the three
musicians” is done
primarily in blues and browns.
6.5段落分析
主题句： innovations， whether practical or aesthetic， are often resisted by the general
population.
推展细节：1. people's objection to the early experiments in the field of
aviation.
2. people's
objection to modern art and music.
无关细节：1. the wright brothers' experiment in flight.
2.picasso's
painting.
显然这不是个好的段落，因为并非所有的推展句都支持主题句。应该把无关的细节删去。下图是一个有统一性的段落的结构图。
图：42110037zw_0007_1
exercise 6-1
directions： in the folowing sentence grouping， circle the letter in front of any detail that does not support the
topic sentence.
topic sentence：my main satisfaction in life comes from the people who are part of
my life.
supporting details：
a. for me a day
is good or bad depending on whether or not i havegooten along well with my
associates.
b. i am not at
all affected by the weather the way some people are.
c. for instance， my father judges his day by
whether or not the skyis blue.
d. on a rainy
day he is always in a bad mood.
e. what counts
for me is to feel human warmth and friendship.
f. my favourite
entertainment is to be with one or two intimate friends， sitting in front of a fireplace
and sharing intimate recollections.
exercise 6-2
directions： read the following paragraph and identify the irrelevant sentences.
1 different people spend their
weekends in different ways.2some enjoy going to the mountains to hike， ski or just relax.3water skiing is much more
difficult than snow skiing.4others prefer going to the beach to enjoy the seashore activities
and to get a suntan.5 some of these people work very hard during the week；others have rather relaxing jobs.6 still others like to relax by
staying home and reading a good book.
topic sentence：________
irrelevant sentences：_______________