LECTURE 1Topic Sentences （主题句）Structure of a Paragraph Three parts: a topic sentence (主题句)supporting sentences (支撑句)a concluding sentence (结论句)Effective Topic SentencesWhat is a topic sentence?A topic sentence introduces the main idea of a paragraph. A topic sentence controls the sentences that follow. A topic sentence makes a point. How is a topic sentence composed?topic sentence = topic + controlling ideaThe Topic of a Topic Sentence The topic presents the general domain of a paragraph. Q: What are the topics of the following sentences? Railway travel in Spain is a nightmare which tourists should know about before embarking a trip.There are several advantages in growing up in a small town. The topic should be well narrowed-down. Q: Which is general and which is specific? City College is completely overcrowded. The cafeteria at crowded City College is one of the most overworked places on the campus. The Controlling Idea of a Topic SentenceThe controlling idea limits and expands the topic by showing a judgment or attitude about the topic. Q: Is the sentence effective? Culture shock has four main stages: excitement, frustration, humor, and adjustment. The controlling idea should be well-focused and leaves room for development. Q: Do they have a sharp focus? Overeating is bad. Abraham Lincoln was the sixteenth president of the USA. Overeating is bad.Overeating contributes to several health problems. Abraham Lincoln was the sixteenth president of the USA. Abraham Lincolns most outstanding quality was his honesty. Exercise A: Identify the topics and controlling ideas of the topic sentences below: People can avoid burglaries by taking certain precautions. There are several enjoyable ways to travel between the US and Queretaro. Animals in danger of becoming extinct come from a wide range of countries. In order to fully explore the wreck of the Titanic, scientists must address several problems. Industrial waste poured into Lake Michigan has led to dramatic changes in its ability to support marine life. To conclude: A good topic sentence is supposed to:Be neither to general nor too narrowHave a limited topic and a well-focused controlling idea Exercise B: Pick out the effective topic sentences and revise the ineffective ones.1.Television discourages communication.2.English is really a very useful tool to us.3.My fathers face is rough. 4.Although Japan and the US have a few similarities, there are greater differences between these nations of the East and West.5.My brother was depressed yesterday for several reasons.6.Living in town has its drawbacks.7.Sleep may well be the third essential components of a long and healthy life.8.Computers play a critical role in modern society.9.I started college after being away from school for seven years.10.In our society food is often connected with recreation.Exercise B: Checking topic sentences for paragraphs. Baseball is a popular sport in the USA. There are two teams of nine players each. Players on one team take turns batting, and the other team tries to put the batters out. The batter hits the ball and then tries to run around the bases and get “home” safely. The other team tries to put the batter out by catching the ball before it hits the ground, throwing the ball to the base before the batter gets there or by tagging the batter with the ball. The batter can stop at any one of the three bases if it is possible to make it “home”.Baseball, a popular sport in the USA, is played in the following way/ according to the following rules. Many students cannot afford a car. The city bus service usually passes the university, so those students can get to class on the bus. Many universities have a special shuttle bus that is provided for student transportation. Some students like to ride to class on bicycles. This is good exercise. Also, it is easier to find a space to leave a bicycle than to find a parking space on a crowded campus. Those students who live close to campus or on campus can enjoy a leisurely walk to their classes. Supply the missing topic sentences:First, you should contact the registration office of the university you want to attend to get the necessary forms and information concerning that particular universitys entrance requirements. Then you must follow the steps outlined in their response. You will probably have to send copies of you high school diploma, get letters of recommendation, and write an essay on why you want to study there. You may have to achieve a certain score on the TOEFL test and have your scores forwarded to the university. Finally, you will have to contact the American embassy to start procedures to obtain a student visa. You may follow the steps below when you apply for an American University.Even though the procedures followed to enroll an American University vary according to each university, some steps are the same.For instance, when I was in kindergarten, I dreamed that my sister killed people with a