separate phrases, clauses, or items in a list

I had fish, vegetables, chicken and rice for dinner.

end a statement

end a question

end a sentence expressing surprise, joy, anger, fear and other strong emotions

give more inf. about the main clause or introduce a list of items

separate two main clauses that are grammatically independent, but have closely related meanings

Heart operations can be dangerous.

Are heart operations dangerous?

It’s so dangerous?

A. I have gained weight: my clothes do not fit. B. I do 3 kinds of sports : basketball, swimming and badminton

Some people lose weight by taking pills; they do not care about their health.