Meaning : A state of difficulty that needs to be resolved.
Example :
She and her husband are having problems.
It is always a job to contact him.
Urban problems such as traffic congestion and smog.
Synonyms : job
Meaning : A question raised for consideration or solution.
Example :
Our homework consisted of ten problems to solve.
Meaning : A source of difficulty.
Example :
One trouble after another delayed the job.
What's the problem?.
Synonyms : trouble