Read the incorrect sentence. Write three to five sentences explaining what kind of run-on sentence it is and how to revise it. My mother and father are both scientists, it must have been my destiny to become interested in biology.

This sentence contains a comma. It has two independent clauses joined only by a comma. One way to revise the sentence is to separate it into two sentences by changing the comma to a period and then capitalizing the word it to start a new sentence.