Final answer:
Introductory phrases do not have their own subject and verb and set the stage for the main part of the sentence. They provide context and introduce additional information.
Step-by-step explanation:
Here are three sentences with introductory phrases starting off with the provided words:
- At the park, children played on the swings.
- When the rain started, we ran indoors.
- According to the weather forecast, it will be sunny tomorrow.
Introductory phrases set the stage for the main part of the sentence and do not have their own subject and verb. They provide context and introduce additional information.