With a deep breath, she took the plunge into the unknown.
Meaning: The girl jumped into the water headfirst, even though she didn't know what was below the surface.
Choice of Words: Plunge means to jump or dive into water headfirst. Unknown refers to something that is not known or understood. With a deep breath suggests that the girl was nervous or anxious about jumping into the water, but she took a deep breath to calm herself down before doing it.
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Related Expressions