the steps for(the procedure for) 步骤、程序
the advantages of(the disadvantages of) ……的优势（劣势）
the ways to(the methods of) 做……的方法、途径
the different sections(parts, kinds, types) of 不同的部分（种类、类型）
the characteristic(traits, qualities) of 特征、特点
the problems of 问题
the precautions of 预防措施
the changes to 变化
Checking topic sentences
Your topic sentence should tell the person who is reading your paragraph what the paragraph is about. Read the following paragraph and decide whether the topic sentence is strong or weak. (The topic sentence is underlined.)
Baseball is a popular sport in the United States. There are two teams of nine players each. Players on one team take turns batting, and 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 impossible to make it "home."
The topic sentence in the paragraph is weak because it tells us that "baseball is a popular sport ", but the rest of the paragraph tells us how baseball is played. A stronger topic sentence would tell us, the readers that the paragraph is going to describe how baseball is played. Here is a stronger topic sentence.
Baseball, a popular game in the United States, is played in the following way. Now the reader knows that the paragraph will describe how baseball is played instead of where it is played or who plays it, or why it is popular.