He smiled broadly at the joke.
Meaning: This means that he formed a smile with his mouth in a manner that was wide and open in response to a funny story or saying that is told to make people laugh.
Choice of Words: Smiled is a verb that means to form a smile with your mouth. Broadly is an adverb that describes the manner in which the smiling is done. Joke is a funny story or saying that is told to make people laugh. When you put them together, "Smiled broadly at the joke" describes the action of forming a smile with your mouth in a manner that is wide and open in response to a funny story or saying that is told to make people laugh.
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Related Expressions