He made a math problem.

This test had too many malicious questions, making it difficult to solve.

It is difficult to find the answer to this big question.

This minor question is too difficult to solve.

I was able to answer all questions correctly.

This is really a good problem, isn't it?

We are preparing a response to your inquiry.

When she said thank you, I replied you're welcome.

He had a doctor look at his oesophagus problem.

How do you solve this problem?