'issue' : an important topic for debate
- when used to describe a person, it refers to personal problems or difficulties that can cause friction in his relationships
'subject' : a person or thing which is being discussed. "The scandal was the subject of conversation around the dinner table of everyone in the town."
- • a person who is the focus of scientific or medical attention or experiment.
- a branch of knowledge studied or taught in a school, college, or university.
- a citizen or member of a country other than its supreme ruler (In the UK, we are subjects of the Queen)
topic : the focus of a conversation; the matter under discussion. (the topic of conversation round a meal table can change as people change the subject of conversation, and they talk about something else.)
matter : a situation or issue under consideration, usual of a serious and important nature eg matters of government, financial matters
Student or Learner