Examples of topic sentences

The following two paragraphs have a topic sentence, but the topic sentence only works well in one of them:

1. Trondheim has many sights worth checking out if you are visiting the city. Perhaps the most famous place to see is the Nidaros Cathedral, situated in the city center. Another old building worth a visit is Stiftsgården. If you want to see the whole city at once, you can visit the Tyholt tower, which has a panorama view of Trondheim.
2. Trondheim has many sights worth checking out if you are visiting the city. The city was established in 997 and was the capital of Norway at one point. Trondheim borders Malvik to the east as well as Klæbu, Melhus and Skaun to the south. Trondheim is also very popular with students, who make up a big part of the population.

In this case, the topic sentence states that Trondheim has many sights you should see. In the first example, the topic sentence is supported by examples and information about various sights. In the second example, the topic sentence is not really supported by the rest of the paragraph at all. On the contrary, the rest of the paragraph only offers information about Trondheim’s history, geography, and demography. This makes the paragraph confusing, because it starts out by introducing one topic, but then goes on to discuss something unrelated to the topic sentence.

Examples of good topic sentences:

• Young people today are used to always having internet access and use the Internet in a variety of situations. For example, it has become very normal to use your mobile phone to buy a bus ticket, communicate via social media or do quick fact checking on the go. All these activities require Internet access and having this access has become so commonplace that most of us take it for granted.
• In football, the referee can stop the play during an attack because of offside. Simply put, the offside rule means that a player on the attacking team cannot be placed behind the last defenseman on the defending team the moment a pass is played to him. The attacking team player can receive the pass behind the last defenseman, but in that case, he must have moved there after the pass was played.
• The price of a real estate object does not only depend on the object’s size and standard, but also the demand of such objects in the area. In other words, two identical apartments can have a different price, because more people are looking for an apartment in one of the areas. When more people are looking for a specific type of object in an area, it will bring the price up, because more people are fighting over the same object. Because of this, you often find yourself paying a lot more for an apartment in Oslo than you would in a smaller city with a lower demand for housing opportunities.