第一段和第三段提到了victims(受害者)，第二段中提到了入室行竊，但是這三段說明的共同問題是人們是否應擁有自己的武器來反對犯罪行為。因此只有選擇(C)才能概括這三段所共同說明的問題，也就是此文的中心思想。

　　二、主題思想應能恰如其分地概括文中所闡述的內容。面不能太窄，即：不足以概括全部內容;但是面也不能太寬，即：包含了文中沒有闡述的內容。

　　例四：

　　Directions: Read the following passage and choose the best central thought

　　Sugar history in the Hawaiian Islands is filled with pioneering. In sailing ship

　　days, Hawaiian sugar growers were many months from sources of supplies and from markets. This isolation built up among the Hawaiian growers an enduring spirit of cooperation. Growers shared with one another improvements in production. Without government aid of any sort, they built great irrigation projects. Without government help, they set up their own research and experiment organization. Pioneering together over the years, they have provided Hawaii with its largest industry.

　　(A) In sailing days, Hawaiian sugar growers were many months away from supplies and markets.

　　(B) Hawaiian sugar growers built their great industry without government help.

　　(C) Hawaiian sugar growers have set up their own research organization and have

　　shared improvements.

　　(D) By pioneering together, sugar growers have provided Hawaii with its largest industry.

　　(A)，(B)和(C)項只是文中提到的各項具體內容，作為主題思想面太窄了，只有(D)項才概括了全文要說明的問題，因此，(D)是該文的主題思想。

　　要求抓主題思想的另一種形式是為短文選擇合適的標題，因為短文的標題常常也體現它所圍繞的主題或討論的中心。因此，為短文選擇標題實際上也反映了對主題思想的掌握。

　　例五：

　　Directions: Read the following and choose the title that best expresses the ideas of the passage.

　　There is a simple economic principle used to determine prices. It is called the law of supply and demand. Supply means the amount of, or access to, certain goods. Demand represents the number of people who want those goods. If there are more goods than wanted, the price of them falls. On the other hand, if the demand for those goods is much greater than the supply, then the price rises. Of course, manufacturers prefer to sell more goods at increased prices.

　　(A) Economic Principles

　　(B) Law of Supply and Demand

　　(C) More Goods, Lower Prices

　　(D) Fewer Goods, Higher Prices