Sentence - a group of words that expresses a complete thought. A sentence consists of two parts: the subject and the predicate
Fragments - a group of words that do not express a complete thought.
exs. - Living in Massachusetts. Eating breadsticks.
Run-ons - a group of words where more than one complete thought is expressed, often joined by a comma.
ex. - He lives on the other side of town, the house he has is yellow.
Subject - tells whom or what the sentence is about. A subject may be one or more words.
Simple subject - the main word in complete subject, usually a noun or pronoun.
ex. - The dog on the bench is a boxer. (Word in italics is the simple subject)
Complete Subject - the main noun or pronoun that the rest of the sentence is about and the words or phrases that modify it.
ex. - The dog on the bench is a boxer. (Words in italics are the complete subject)
Compound subject - two or more connected subjects that share the same verb, usually connected by the conjunctions "and" or "or."
ex. - The dog and cat fight constantly. (Words in italics are the compound subject)
Remember!: In a question the subject may not come first.
ex. - Is the subject this? (The italicized word is the subject.)
To find the subject, turn the question in to a statement.
ex. - The subject is this.
Remember!: The subject can be implied in an imperative sentence (a command)
ex. - Run! (which is really: "(You ) run!")