Voldemort trying to get the stone, but Harry stopping him.
I would actually use them together: benefit from someone's expertise.
For example,: While building this bridge, we could benefit from the architect's expertise.
or:
Let's invite Sarah, she knows a lot about cooking, we could benefit from her expertise!
A cliche is a well-worn phrase used in conversation or in writing that has lost it's meaning. It's been overused. For example, "She was frightened to death to pet the pitbull..." "frightened to death" is the cliche.
