Part One The Topic Sentence and the Rulesfor Writing the Topic Sentence
A topic sentence is the sentence that states the topic that the paragraph will develop.A good topic sentence has the following features.
1.A topic sentence is a complete sentence；that is, it should contain a subject (主语) and a verb (动词).
1) Trees are useful to man in three very important ways.
2) New York has great entertainment.
3) There are three techniques that scientists use to discover the true age of a fossil.
4) Give students a chance to grow.
5) Cleaning your room is not difficult if you follow some simple guidelines.
6) Listed below are a number of tips on how to get along with people.
2.A topic sentence is usually a statement, not a question.
1) Do the colors of the U.S.flag have unique symbolic meanings?
2) The colors of the U.S.flag have unique symbolic meanings. (more common)
3.A topic sentence should not be too broad or too narrow.If it is too broad, you will not be able to develop the topic in one paragraph.If it is too narrow, you won't have enough to write in the rest of the paragraph.
1) I love all sorts of sports. (too broad)
2) Swimming is my favorite hobby. (too narrow)
3) Exercising every day has several positive effects on my health. (appropriate)
4.A topic sentence has two parts: the topic and the controlling idea.The topic refers to what the paragraph is about, and the controlling idea is the writer's opinion or attitude from which the reader can ask questions about: How? Why? In what ways? What are they? etc.Note how each of the following topic sentences states both the topic and the controlling idea.The topic is underlined, and the controlling idea is enclosed in parentheses.
1) Cars can be used in (many different situations).
From Sentence 1) , we know that the paragraph is going to discuss something about“cars” (the topic). The question a reader can ask from the writer's opinion is“How can cars be used in different situations? ” (controlling idea).