A topic sentence makes a point. The rest of the paragraph proves or explains it with supporting details.
| Kind of support | Example for “Our town needs a dog park.” |
|---|---|
| Fact | The town has 1,200 licensed dogs and no fenced place to run them. |
| Example | Last spring, two loose dogs ran into traffic on Pine Street. |
| Reason | Dogs that get exercise bark less and sleep better. |
| Detail | The empty lot behind the library is flat, shady and already fenced on two sides. |
Key idea
Supporting details are facts, examples, reasons and details that show the main idea is true. Each one must connect to the topic sentence and add something new.
Why it works
A reader has no reason to accept a point that stands alone. Details turn a claim into something the reader can see and check. They also keep the writing specific: “dogs ran into traffic on Pine Street” sticks in the mind; “it is unsafe” doesn’t.
Worked example: Support or restatement?
Topic sentence: “Tomatoes are easy to grow.” Which detail supports it: (a) “Growing tomatoes is not hard.” or (b) “A single plant in a sunny pot can produce fruit all summer.”
- (a) says the same thing as the topic sentence in other words. It adds nothing.
- (b) gives a specific fact a reader can picture.
- Support must add new information.
Answer: (b).
Worked example: True but off the point
Same topic. Does “Tomatoes first grew wild in South America.” support it?
- It is a fact about tomatoes.
- But it says nothing about whether they are easy to grow.
- A detail can be true and still not support this point.
Answer: No. It is true but off the point.
Common mistake
Adding details that are true but off the point, or repeating the topic sentence in new words. Test each sentence with the question: does this help prove or explain the topic sentence, and does it say something new?