Answer;
Sara suddenly became very ill; therefore,she went to see her doctor.
Explanation;
A semicolon is most commonly used to link (in a single sentence) two independent clauses that are closely related in thought.
When used to join two or more ideas (parts) in a sentence, those ideas are then given equal position or rank.
You cannot use a semicolon to list off objects, such as letter a and b.
You also can't use one in the middle of a sentence, like the third sentence.
