Punctuation is the system of signs or symbols given to a reader to show how a sentence is constructed and how it should be read. Sentences are the building blocks used to construct written accounts. They are complete statements. Punctuation shows how the sentence should be read and makes the meaning clear. Conjunctions are words that join together other words or groups of words. A coordinating conjunction connects words, phrases, and clauses of equal importance. The main coordinating conjunctions are and, or, and but. They bought apples, pears, and oranges. You can wait either on the steps or in the car. An interjection is a word or phrase that is grammatically independent from the words around it, and mainly expresses feeling rather than meaning. Oh, what a beautiful house! Uh-oh, this looks bad. Well, it's time to say good night.