pluralproblems
noun: a matter or situation regarded as unwelcome, harmful, or wrong and needing to be dealt with and overcome
The main problem with the car is its faulty transmission.
noun: a question proposed for solution or discussion, especially in mathematics or science
The students were asked to solve a difficult algebra problem.
adjective: denoting a person or group that is difficult to deal with or causes trouble
He was a problem child in school, often disrupting the class.