What is the proper use of dashes within a sentence to set apart something surprising?

Match the definition to the word. 1. person or group opposing or hostile to another person or group propaganda 2. arranged in the order in which the events happened spatial 3. based upon reason; a rational approach to something logic 4. a method or system used to accomplish something adversary 5. having to do with space technique 6. coming one after another, in series, or in order chronological 7. the spreading of opinions or beliefs implied 8. suggested, indicated, or understood without express statement sequence