他破解了难题。
He solved the hard problem.
to break (a bond, constraint etc); to explain; to unravel
Every character draws itself, stroke by stroke. Then grab the brush: trace it yourself and hear the word when you finish.
Nice writing!
Chinese words snap together like bricks. Every word below shares a character with this one, so you are already halfway to knowing it.
他破解了难题。
He solved the hard problem.
谜团破解了。
The mystery is solved.