Maintain, to preserve or keep things as they are.
Our quality is excellent, so your job is to maintain our high standards and improve them if you can.
These historic buildings are very old and need to be maintained.
Disrupt, to cause disorder or confusion.
Smartphones have disrupted the way we live our lives.
Investors want to invest in companies that disrupt the way things are done.
Settle, to calm things down or end a conflict or disagreement.
He is too upset to think clearly, so he needs to settle down.
If we can't agree, we'll have to go to a court to settle our differences.
Solve, to figure out or find the answer or solution to a problem.
The problem is difficult, so we need to find a way to solve it.
We can't solve that problem without using a computer.
Prove, to use evidence or logic to support an idea.
The police had to release him because they couldn't prove that he committed the crime.
The best way to prove that something can be done is to do it.
(During the prisoner exchange, one of the prisoners tried to escape.)