Final answer:
Summary is used by writers to convey background information and provide a brief overview of the main points in a text.
Step-by-step explanation:
The common reason writers use summary is to convey background information. Summary is a way for writers to provide a brief overview or synopsis of the main points or events in a text. It allows readers to quickly grasp the important details without having to read the entire piece. For example, in a news article, the first paragraph often includes a summary of the key points of the story.
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