To start smiling.
Even though she scolded me for disrupting class, I’m pretty sure I saw Ms. Miller break into a smile for a second.
Frequently Asked Questions (FAQs)
The idiom ‘break into a smile’ means “to deal with a difficult situation without being harmed or damaged”
Example usage of idiom ‘break into a smile’: Newspapers have weathered the storm of online information by providing news online themselves.