写作 Chapter Three Base2.ppt

Chapter Three Producing Effective Sentences,Base 2:Coherence,Part II Building Good Sentence,Base 2:Readability,1.Coordinating to Relate Equal Ideas,2.Subordinating to Distinguish the Main Idea,3.Choosing Clear Connectors,4.Using Parallelism,Understanding Coherence,Understanding Coherence,Effective communication requires the fitting of thoughts together according to their relative importance so that the readers attention stays focused on the major points.There are many ways to improve coherence.One of them is through skillfully manipulating Syntactic Structures for Sentence Coherence:,coordination subordination choosing clear coordinators using parallelism,Understanding Coherence,Activity,Make a study of the following sentences to see how coherence is improved through the above sentence combining skills.,Understanding Coherence,Sentence 1,Car insurance is costly,but medical insurance is almost a luxury.,Comment:We can coordinate the facts and ideas that we wish to emphasize equally,such as the thoughts about insurance in this sentence.We can coordinate the information in words,phrases,and clauses by joining them with the coordinating conjunctions such as and,but,or,nor,for,so,and yet;by joining them with conjunctive adverbs such as however,moreover,and therefore.,Understanding Coherence,Sentence 2,Because accidents and theft are frequent,car insurance is expensive.,Comment:We subordinate lesser facts and ideas to the ones we wish to emphasize.In this sentence,the clause beginning with Because is subordinate to the main clause.Subordinated information may be very important to the total meaning of the sentence,but,compared with one in the main clause,it is less important.We can also subordinate information by expressing it in clauses introduced by subordinating conjunctions such as although,because,if,when,where,while,or relative pronouns,who,which,that;or by expressing it in phrases and single words.,Understanding Coherence,Below are some commonly used conjunctions,Understanding Coherence,Sentence 3,Newspapers may someday be brought to your home,not by paper carriers,but by computers.Subscribers will simply punch in a code,and the machines will display the desired pages.,Comment:Connecting words are used to tie ideas together.Most of them signal specific and definite relationships;for instance,the coordinating conjunction but clearly indicates contrast while the coordinating conjunction and helps hold coordinate ideas together.,Understanding Coherence,Sentence 4,Recycling old buildings both conserves our resources and preserves our past.,Comment:In the sentence above,the two parts of the compound predicate are both coordinate and parallel.We can coordinate the information by expressing them in the same kind of grammatical construction like parallelism.,Understanding Coherence,Coordination,The following provides some guidelines for managing coordination effectively.,1.Coordinating to Relate Equal Ideas,Linking sentences and ideas with coordinating conjunctions enables the reader to see the relations between them more easily.,Compare the following two passages.,Activity,Coordinating to Relate Equal Ideas,Passage 1,We should not rely so heavily on coal,oil,and uranium.We have a substantial energy resource in the moving waters of our rivers.Smaller streams add to the total volume of water.The resource renews itself.Coal and oil are irreplaceable.Uranium is also irreplaceable.The cost of water does not increase much over time.The costs of coal,oil,and uranium rise dramatically.,Coordinating to Relate Equal Ideas,We should not rely so heavily on coal,oil,and uranium,for we have a substantial energy resource in the moving waters of our rivers and streams.Coal,oil,and uranium are irreplaceable and thus subject to dramatic cost increases;water,in contrast,is self-renewing and more stable in cost.,Passage 2,Coordinating to Relate Equal Ideas,Comment:The information in both passages is essentially the same,but the second is shorter and considerably easier to read and understand.Whereas the first passage strings ideas together in short,simple sentences without relating them to each other,the second passage builds connections among coordinate ideas:the availability of water in rivers and streams(first sentence);the relation between renewal and cost(second sentence);and the contrast between water and the other resources(both sentences).,Coordinating to Relate Equal Ideas,Points to Remember:,（1）Avoiding Faulty Coordination,Faulty coordination occurs when no logical connection seems to exist between two coordinated statements or when the stated connection contradicts common sense.Sometimes faulty coordination occurs because the writer omits necessary information.,Coordinating to Relate Equal Ideas,Example 1,Faulty：Jacob is a foster child and has to go to the dentist often.Revised：Jacob is a foster child whose biological parents neglected his teeth;consequently,he has to go to the dentist often.Revised：Because Jacob is a foster child whose biological parents neglected his teeth,he has to go to the dentist often.Comment:Often,as the last example above shows,the intended relation between clauses can be clarified by subordinating one of the ideas if it modifies or explains the other one.,Coordinating to Relate Equal Ideas,Example 2,Faulty：John Stuart Mill was a utilitarian,and he believed that actions should be judged by their usefulness or by the happiness they cause.Revised：John Stuart Mill,a utilitarian,believed that actions should be judged by their usefulness or by the happiness they cause.,Coordinating to Relate Equal Ideas,（2）Avoiding Excessive Coordination,A stringy compound sentencea sequence of main clauses linked with coordinating conjunctionscreates the same effect as a series of simple sentences:It obscures the relative importance of ideas and details.,Coordinating to Relate Equal Ideas,Example 1,coordination：We were near the end of the trip,and the storm kept getting worse,and the snow and ice covered the windshield,and I could hardly see the road ahead,and I knew I should stop,but I kept on driving,and once I barely missed a truck.,Excessive,Comment:This sentence contains two main assertions:the storm kept getting worse and I kept on driving.All the rest is detail elaborating on these simple statements.Such a loosely compounded sentence needs subordination so that main assertions and supporting detail are distinct.,Coordinating to Relate Equal Ideas,Revised：As we neared the end of the trip,the storm kept getting worse,covering the windshield with snow and ice until I could barely see the road ahead.Even though I knew I should stop,I kept on driving,once barely missing a truck.,Comment:Be careful not to overuse so as a coordinating connector.,Coordinating to Relate Equal Ideas,Example 2,Coordination：Jim had an examination that day,so he came home late,so he missed seeing the fire,so he was not able to describe it to us.,Excessive,Comment:As with other modes of excessive coordination,the best way to revise such sentences is to separate the main statement from dependent details.,Revised：Jim was not able to describe the fire to us because he had an examination that day and arrived home too late to see the fire.,Comment:Excessive coordination is not always as obvious as it is in the two examples above.,Coordinating to Relate Equal Ideas,Example 3,Coordination：A man came out of the liquor store.He wore a pair of frayed corduroy pants,and he wore a brown sweater.He started toward a blue car,and the police arrested him.,Excessive,Revised：When a man wearing frayed corduroy pants and a brown sweater came out of the liquor store and started toward a blue car,the police arrested him.,Coordinating to Relate Equal Ideas,Comment:The passage above contains only two compound sentences,but they still connect facts so loosely that the reader is left to distinguish their importance.Using subordination to rewrite this passage shows clearly which ideas are important and which less important.The essential fact that the police arrested the man becomes the main clause,and all other details are incorporated into a single subordinate when clause.,Coordinating to Relate Equal Ideas,Activity,Exercises for Coordination,Combine sentences in the passages below to coordinate related ideas in the way that seems most effective to you.You will have to supply coordinating conjunctions.,（1）Everyone read some fairy tales as a child.Everyone remembers some.Most people think they are only for children.They express the deepest fears and desires of children.They also express the deepest fears and desires of adults.Adults read them to children.They should read them for themselves.,Coordinating to Relate Equal Ideas,（2）Henry Hudson was an English explorer.He captained ships for the Dutch East India Company.On a voyage in 1610 he passed by Greenland.He sailed into a great bay in todays northern Canada.He thought he and his sailors could winter there.The cold was terrible.Food ran out.The sailors mutinied.The sailors cast Hudson adrift in a small boat.Eight others were also in the boat.Hudson and his companions perished.,Coordinating to Relate Equal Ideas,Example,My dog barks,and I have to move out of my apartment.Because my dogs barking disturbs my neighbors,I have to move out of my apartment.,The dean was furious,and she let the police know it,but they refused to listen,and they began patrolling the campus.,(2)Our fire fighters went on strike and are now in jail because they want a written contract and better working conditions and also they want their lieutenants in the union,but the town council opposes the fire fighters demands,so the situation is at a stalemate.,Coordinating to Relate Equal Ideas,(3)The dogs escaped from the pen because the keeper forgot to secure the latch,and the dogs wanted freedom,and they got it by running away,and it took the rest of the day to find them.,(4)The weather in March is cold and rainy,but sometimes it is warm and sunny,and the inconsistency makes it impossible to plan outdoor activities,yet everyone wants to be outdoors after the long winter.,(5)The gun sounded,and I froze,but an instant later I was running with a smooth,pumping motion,and I knew I would win the race.,Coordinating to Relate Equal Ideas,(6)The citizens of Vermont are determined to preserve their environment,and they have some of the nations toughest antipollution laws.,(7)Two days last month were legal holidays,and the school held classes as usual.,(8)Registering for classes the first time is confusing,and you have to find your way around,and you have to deal with strangers.,Coordinating to Relate Equal Ideas,(9)Robert was due to arrive at lunchtime,and he called just before dinner.,(10)Air traffic in and out of major cities increases yearly,and the congestion is becoming dangerous,but the current regulations are inadequate,and they cannot control even the present traffic.,Coordinating to Relate Equal Ideas,2.Subordinating to Distinguish the Main Idea,Understanding Subordination,Subordination is crucial for distinguishing principal ideas from supporting information.,Activity,Study the sentence below to see how crucial subordination is in building good sentences.,Subordinating to Distinguish the Main Idea,Sentence,In recent years car prices have increased,and production costs have increased even more,and carmakers must contend with lower profits.,Comment:In the sentence below,no distinction of this kind exists.,Three facts have been given:car prices have increased,production costs have increased,and profits are lower.By loosely coordinating these three facts,the writer suggests some relation among them.But in recent years and even more provide the only explicit relations.We do not know which fact the writer sees as most important or how the other facts qualify or support it.,Subordinating to Distinguish the Main Idea,Revision 1:Because production costs have increased even more than car prices in recent years,carmakers must contend with lower profits.,Revision 2:Although car prices have increased in recent years,production costs have increased even more,so that carmakers must contend with lower profits.,Revision 3:When production costs increase even more than car prices,as they have in recent years,carmakers must contend with lower profits.,Subordinating to Distinguish the Main Idea,Comment:In these revisions the words because,although,so that,when,and as indicate specific cause and effect relations among the three facts.Each sentence makes clear that carmakers profits decline when increases in production costs outstrip increases in prices,but the emphasis varies from one version to another.,Subordinating to Distinguish the Main Idea,Conclusion:Using subordinate clauses to distinguish main ideas from supporting information is the first and most important step toward writing effective sentences.In general,a subordinate clause will give greatest importance to subordinate detail;verbal phrases,appositives,and absolute phrases will give somewhat less weight;prepositional phrases still less;and single words the least.,Subordinating to Distinguish the Main Idea,Activity,Study the examples below to see the differences among subordinate constructions.,Example 1,Old barns are common in New England.They are often painted red.separate sentences,Example 2,Old barns,which are often painted red,are common in New England.subordinate clause,Subordinating to Distinguish the Main Idea,Example 3,Old barns,often painted red,are common in New England.verbal phrase,Example 4,Old red barns are common in New England.single word,Example 5,Jones has been without work for six months.He is having trouble paying his bills.separate sentences,Subordinating to Distinguish the Main Idea,Example 6,Because Jones has been without work for six months,he is having trouble paying his bills.subordinate clause,Example 7,Having been without work for six months,Jones is having trouble paying his bills.verbal phrase,Example 8,Out of work for six months,Jones is having trouble paying his bills.prepositional phrase,Subordinating to Distinguish the Main Idea,Example 9,The horse looked gentle.It proved high-spirited and hard to handle.separate sentences,Example 10,Although the horse looked gentle,it proved high-spirited and hard to manage.subordinate clause,Example 11,The horse,a gentle-looking animal,proved high-spirited and hard to manage.appositive,Subordinating to Distinguish the Main Idea,Example 12,The gentle-looking horse proved high-spirited and hard to manage.single word,Example 13,The old factory now manufactures automobile transmissions.It stands on the south side of town and covers three acres.separate sentences,Subordinating to Distinguish the Main Idea,Example 12,The old factory,which stands on the south side of town and covers three acres,now manufactures automobile transmissions.subordinate clause,Example 13,The three-acre factory on the towns south side now manufactures automobile transmiss