Cause and effect, sometimes called causal analysis, explores the cause-and-effect relationship between two (or more) subjects or items.When you discuss the reasons producing something, you are analyzing the cause；when you discuss the results produced by something, you are analyzing the effect.A causal analysis essay usually focuses on either the causes or the effects of a situation or an event.Now read the following two model essays below, and identify which essay focuses on causes and which essay focuses on effects.
Model Essay One
The Extinction of Dinosaurs
For almost 140 million years, dinosaurs and other large reptiles ruled the land, sky and sea.Dinosaurs came in sizes and shapes suited to every corner of the world.Then approximately 65 million years ago, these huge reptiles died out and mammals took over the Earth.Few mysteries have ever excited the imaginations of scientists as much as this great extinction that killed off all the dinosaurs.Over the years, scientists have developed numerous theories to explain the causes of the disappearance of the dinosaurs and other great reptiles.Three possible causes are a change in the Earth's climate, disease, and the Earth's collision with a large asteroid (小行星).
Some scientists believe that the number of dinosaurs declined and eventually disappeared due to a change in the Earth's climate.During the Cretaceous (白垩纪的) period, the climate was tropical.Research indicates that at the end of the Cretaceous period, the temperature dropped and the climate became much colder.For this reason, many of the plants that the plant-eating dinosaurs ate died.The death of the plants would cause many of the plant-eaters to die, too.As the plant-eating dinosaurs died off, so did the meat-eaters who fed on them.The colder climate may have caused problems for the dinosaurs in other ways, too.Because of their size, many dinosaurs were too big to hibernate in dens (洞穴). They also lacked fur or feathers for protection against the cold.As a result, the dinosaurs were unable to adapt to the new cold conditions.
Another possible cause for the extinction of dinosaurs is disease.Some scientists think that when large groups of dinosaurs migrated across land bridges, they infected one another with new illnesses across continents, and were subsequently killed off.As the Cretaceous period went on, more and more land bridges started to appear on the Earth.Because the oceans were drying up and dinosaurs were able to walk across the land bridges, they began to spread new diseases.
A third cause for the extinction of dinosaurs is the asteroid theory.According to this theory, the extinction was much more sudden and catastrophic.In the late 1970s, scientists discovered evidence for the abrupt end to the Age of Dinosaurs.Dr.Louis Alvarez and his colleagues arrived at a revolutionary hypothesis to explain the extinction of dinosaurs.They suggested that about 65 million years ago, the Earth was struck by a huge asteroid.The asteroid was destroyed in the explosion, and billions of tons of dust were thrown up into the air.A thick cloud of dust blocked out sunlight for a long time.Consequently, many plants died without sunlight.The lack of plants killed off many of the plant-eating dinosaurs, which then caused the death of the meat-eating dinosaurs that preyed on them.The darkness caused temperature to fall below freezing point for many months.As a result of the sudden change in climate, the dinosaur populations became smaller and smaller.
It seems that no one theory adequately explains why dinosaurs died out.Perhaps dinosaurs simply could not adjust to the changes that were taking place on the Earth toward the end of the Cretaceous period.Perhaps it was a combination of causes that contributed to the end of the Age of Dinosaurs.
Model Essay Two
Do It!
Some do it to music；some do it quietly.While some do it in the privacy of their own homes, others do it in gyms.For some, they do it in the morning, others at night.But no matter where or when, millions of people all over the world do it-and that is aerobic exercise.The benefits of regular aerobic exercise are great because it can help people improve the functions of their heart ＆ lungs, prevent bone degeneration, and reduce stress.
Probably the most immediate effect of aerobics is improved heart and lung functions.When a person exercises long and hard enough, the heart pumps faster and blood is circulated well throughout the body.Since the heart is a muscle, exercise serves to strengthen it.As the heart becomes stronger, a person's stamina improves as well as his energy level.The same is true of the lungs.A person can get positive results within a few weeks just by walking briskly for 30 minutes three or four times a week.
The second physical benefit of regular aerobic exercise takes a little bit longer to achieve, but is well worth the effort, particularly for women.Exercise can help prevent the crippling bone degeneration called osteoporosis (骨质疏松症). Osteoporosis is a gradual process of bone loss that occurs naturally as people grow older, but it can be halted by regular aerobic exercise.Exercise actually helps increase bone mass, and is said to be the best preventive measure to avoid osteoporosis.
One more positive effect about aerobic exercise is that it helps a person alleviate stress.For example, aerobic exercise can make a person feel more relaxed, so he is capable of handling difficulties.That is, when a person exercises, his blood circulation improves and he burns off the adrenalin (肾上腺素) that stress causes the body to produce.Also, exercise can help a person get rid of his stress after sufficient aerobic exercise, because his body produces beta-endorphins, which are natural stress-relieving chemicals.
To summarize, aerobic exercise is an economical method to make a person healthy within weeks.Since aerobic exercise does not require much time or effort, everybody should get enough exercise.Instead of watching television so much at home, a person will be better off walking or cycling.
Now, let's read a causal analysis essay written by a Chinese student.
Why I Enjoy Travel
Travel, just like a magic water-color-brush, paints my life colorful and joyful.When I first stepped out of the city where I was born and grew up, I immediately loved the feeling of getting in touch with the outside world.Since then, I have always been planning some interesting trips.I enjoy traveling, for it can broaden my perspectives, develop my independence, and improve my health.
First, travel is an effective way to enrich my knowledge.In different cities and countries, the cultures and customs vary greatly.For example, a cow is a holly animal to India；Scotland men will wear skirt on their traditional holidays.I have been to some cities in China.Comparatively speaking, although people all speak Chinese, their dialects differ from each other.Besides, people living in different areas seem to display distinct personalities.The southerners tend to be gentle and reserved；the northerners, bold and straightforward.Therefore, through meeting with local people, I can learn their dialects, understand their cultures, and gain new knowledge.
Second, travel provides me with an opportunity to be more self-reliant.Before setting off, I have to make a travel plan, book a plan ticket, make a hotel reservation and collect information about the place I will visit.All will have to be done by myself.While traveling, I have to solve the problems that may occur unexpectedly.The moments when I lose my purse or when I cannot get a return ticket, I can depend on nobody but myself.Through these seemingly trivial experiences in travel, I have become more and more confident in dealing with unforeseen difficulties in life.
Last, travel can contribute greatly to my health in two ways.For one thing, it involves a lot of exercises such as swimming, skating, climbing mountains, which are good to my health.For another thing, since travel brings fun and keeps me in good mood, it releases my work pressure and has positive effect on my mental health.In brief, travel benefits me mentally and physically.
In summary, each time in my trip, I can acquire new knowledge, improve my ability and better my health condition.If time and money permit, I hope to make more journeys.Meanwhile, I wish, my dear friends, you can come and join me.Let's share the pleasures from travel.
* * * * * *
To write a well-organized causal analysis essay, you should follow the guidelines below.
1.Try to control your prejudices in your causal reasoning.For example, concluding that the reason why one of your classmates failed his final exam was that his teacher didn't like him can be irresponsible reasoning.You should not blame his teacher simply because you and your classmate are close friends.Instead, you should explore all the possible reason (s) behind his failure.Without a thoughtful and thorough analysis, your reasoning could become superficial and convince no one.Before judging a situation or an event too quickly, investigate your own biases, especially when you deal with your own problems or beliefs.
2.Avoid oversimplification in writing a causal analysis essay.To claim, for example, that “our planet's pollution problems could be solved if we all recycled” is a statement which oversimplifies a complex issue.Most complex issues have more than one cause or effect, so make your analysis as complete as possible.
3.Limit your essay to a discussion of the most immediate, most important factors.A situation or an event may have several causes or effects；however, you do not have to discuss remote and minor causes or effects in an approximately 300-word essay.In some cases, you can discuss some remote or minor causes or effects, but do so reasonably.Carefully selecting your material can be a great asset when you are writing a causal analysis essay.
4.Arrange your discussion of causes or effects according to one of the most common principles: from the immediate to the remote, from the local to the national, from the obvious to the subtle, from the critical to the less significant, from the major to the minor, from the most important to the least important, etc..Of course, you can also arrange your discussion the other way round.The options are numerous, but you should present your discussion in the order that most clearly and effectively presents your ideas.
Practice 5-3-1
Look at the list of items below.The items in the left column may be causes or effects of the items in the right column, but the items are mixed up.
1) jogging
a) heavy rain and strong winds
2) broken home
b) traffic accidents
3) absence from class
c) decreased college attendance
4) icy road conditions
d) poor profits
5) the patient's death
e) good health
6) soil erosion
f) loud noise
7) eating too much sugar
g) juvenile delinquency (青少年犯罪)
8) ineffective management
h) tooth decay and obesity
9) lack of scholarships
i) failed exams
10) deafness
j) delayed medical treatment
After you have read the items above, complete the following tasks.
Step 1.Match the words in the two columns, and determine the relationship between each pair.For example, jogging and good healthform a pair.Joggingis the cause；good healthis the effect.
Step 2.Write a sentence about each pair, making the items in the left column the subject of your sentence.For example: Jogging can lead to good health.
Step 3.Write a sentence about each pair again, but this time make the items in the right column the subject of your sentence.For example: Good health results from jogging.
Answers will vary.
Practice 5-3-2
Write sentences showing a cause-and-effect relationship.Use the information given in parentheses.Read sample sentences before writing your own.Answers will vary.
1.I have learned to appreciate English literature thanks to a wonderful teacher./ Thanks to technological advances, the world is getting smaller every day./ Thanks to your carelessness, those important documents have been lost.
(thanks to)
2.Delay could give rise to further problems./ The President's absence from the dinner has given rise to speculation (猜疑) about his health.
(give rise to)
3.Layoffs and downsizing accounted for nearly half of all forced retirements./ Despite progress in diagnosis and treatment, cancer continues to account for more than a half million deaths each year in the United States.
(account for)
4.Professor Hawking's speech has indicated that science has a very strong impact on the everyday life of scientists as well as non-scientists./ Organizers of Earth Hour (全球熄灯一小时环保行动) said that while switching off a light for one hour would have little impact on carbon emissions, the fact that so many people were taking part showed how much interest and concern at the climate crisis had taken hold (深入人心).
(have an impact on)
5.Marsha attributed her success to her husband's generous support./ The decrease in crime can be attributed to a rise in the number of police officers.
(attribute… to…)
6.Wealth usually goes hand in hand with power./ Inspiration and perspiration always go hand in hand.
(go hand in hand with/…and…go hand in hand)
7.Chinese are experiencing increasing mental stresses as a result of a faster pace of life and rising competition./ Up to 25% of people who use portable music devices will suffer hearing loss as a result of listening to their players at“excessive and damaging level”.
(as a result of)
8.Psychological and emotional reactions will trigger physical responses./The trigger for the riot was the deaths of two teenage boys in a motorbike crash with a police car.
(trigger)
9.Scientists link dangerous global temperature increase to the greenhouse effect./ Obesity has been linked to a variety of cancers, including colon (结肠) , breast, kidney and pancreatic (胰腺的) cancer.
(link…to…)
10.It is exceedingly (极其地) difficult to establish a causal link between global warming and extreme weather events./ In 1980s, a link was established between ozone depletion and the use of CFC (氟利昂) gases.
(establish a link between…and…)
Practice 5-3-3
The following essay entitled Why Are the Same TV Commercials Used over and over Again? has neither the introductory paragraph nor the concluding paragraph.Read the three body paragraphs carefully, and then write an appropriate introductory paragraph and a concluding paragraph for this essay.Listed below are some useful expressions to help write your thesis statement:
1) There are three (two, four, several, many) causes of (reasons for, effects of) _________.
2) There are three (two, four, several) major reasons why_________.
3) Listed below are three (two, four, several) major reasons why_________.
4) _________ have (two, four, several, many) effects on_________.
Answers are provided only as suggestions.
Why Are the Same TV Commercials Used over and over Again?
________________________________________
________________________________________
________________________________________
The first reason is simply a matter of money.The production of even a 30-second commercial may cost as much as $150, 000.Obviously, it would be far too expensive for a company to produce a completely new advertisement every day, or even every week.Besides, if a new advertisement is produced to replace the old one, the total cost of it will be eventually added to the cost of the product.Yet, consumers do not like to pay more money for the same product.
The second reason is to make sure that as many people as possible will see the advertisement.The more often a commercial is shown on TV, the more people will have a chance to see it.People who watch a lot of television will see the same commercial many times-and will probably become bored by it-but people who watch television less often or confine their viewing to a few favorite programs may also see the commercial at least once or twice.
The third reason is the belief that repetition can help imprint the message on the mind.Some advertisers think that the more frequently an advertisement is shown on TV, the deeper impression it can make on TV viewers.They strongly believe that repetition-even to the point of irritation-is good because irritation itself is supposed to make people remember the product.
________________________________________
________________________________________
________________________________________
Practice 5-3-4
Read the following three topic sentences from the essay topic Three Major Problems in Chinese Examination System.Develop each topic sentence with examples.Answers will vary.
Three Major Problems in Chinese Examination System
First, the exam-centered educational system places too much emphasis on test scores._________________________________
Second, driven to memorize mechanically rather than to think creatively, some students believe that study is boring._________________________________
Last, judging an examinee's potential by a single test is not fair at all._________________________________
Practice 5-3-5
Study the following essay topic carefully, and complete the tasks below.
Step 1.Brainstorm to gather as many ideas as you can about this essay topic.
Step 2.Divide all your ideas into three general groups (cross out the ideas that do not fit any of the groups) , and then write a good thesis statement.
Step 3.Write the introductory paragraph, the three topic sentences of the body paragraphs, and the concluding paragraph.
Essay topic: Why people collect books?
Answers are provided only as suggestions.
Practice 5-3-6
To write a causal analysis essay, you have three choices to make in terms of your focus: causes, effects, or both causes and effects.The emphasis you choose will depend on your essay topic.Choose one of the following essay topics, and write a causal analysis essay with the appropriate number of body paragraphs.After you finish your essay, check it against the Causal Analysis Essay Checklist at the end of this practice.
1.In modern-day China, many people are in pursuit of tangible things such as spacious apartments and luxurious cars.In your opinion, what can account for such a phenomenon?
2.Discuss why campus romances, in some cases, end in failure.
3.China has opened its door to the outside world for more than three decades.Discuss some obvious effects of the contacts between China and Western countries.
4.The past three decades have witnessed an increasing divorce rate in China.What might be causing spouses to separate?
5.Resignation shouldn't be made in haste.
6.Discuss why a place is so special to you. (Specify)
7.Describe your favorite music (sport, book, etc.) and why it appeals to you.
8.Discuss why continuing education is necessary for adults.
9.Describe a success (or a failure) you once had, and discuss its causes and/or effects.
10.Discuss the causes or effects of quitting a job.
11.Discuss the causes or effects of a disagreement you had with your classmate (or teacher, colleague, boss, spouse, child, a close friend, etc.).
12.Identify two or three of the heroes you have looked up to since your childhood.Provide reasons.
13.Explain why you think being a young person today is more difficult than it was 20 years ago. (Specify)
14.Discuss some of the major reasons why some couples in China prefer not to have children.
15.Discuss the effects of an important idea or discovery in your field of study. (Specify)
Causal Analysis Essay Checklist
1.Does your causal analysis essay focus on the causes, or the effects, or both causes and effects?
2.If your essay focuses on causes, have you analyzed the causes in enough detail?
3.If your essay focuses on effects, is your analysis insightful and sufficient?
4.If your essay focuses on both causes and effects, have you given adequate attention to both causes and effects?
5.When you explore the cause-and-effect relationship between two (or more) subjects or items, is your causal reasoning objective or biased?
6.Has your essay avoided the problem of oversimplification?
7.Does your essay discuss the most immediate, most important causes and/or effects?
8.Have you arranged your discussion in the order that most clearly and effectively presents your ideas?
Practice 5-3-7
1.Find an essay topic with which you are quite familiar, and write a causal analysis essay.
2.Find an essay topic related to your study, your job, or your field of research, and write a causal analysis essay.