not sure what the difference between a simple subject, simple predicate, complete subject and a complete predicate are

The simple subject is a noun or pronoun. The simple predicate is the verb.

Example:
Katy is working.
Katy is the simple subject.
is working is the simple predicate.

The complete subject is the simple subject and its modifiers. The complete predicate is the verb plus other words that go with it.

The man in the blue car almost ran a red light.

Complete subject:
The man in the blue car
Complete predicate:
almost ran a red light.

http://www.chompchomp.com/terms/subject.htm

http://grammar.about.com/od/grammarfaq/a/What-Is-A-Predicate.htm

I'm here to help! Understanding the differences between a simple subject, simple predicate, complete subject, and complete predicate is important for grasping the structure of a sentence.

1. Simple Subject: The simple subject is the main noun or pronoun that the sentence is about. It represents the subject of the sentence and answers the question, "Who or what is performing the action?" To identify the simple subject, ask yourself who or what the sentence is talking about.

Example: "The dog chased the ball."
The simple subject in this sentence is "dog" because it is the noun that the sentence is about.

2. Simple Predicate: The simple predicate, also known as the verb, is the action or state of being performed by the subject. It answers the question, "What is the subject doing?" To identify the simple predicate, ask yourself what action the subject is performing.

Example: "The dog chased the ball."
The simple predicate in this sentence is "chased" as it is the action being performed by the subject "dog."

3. Complete Subject: The complete subject includes the simple subject along with all the words that modify or describe it. It provides a broader context for the main subject and includes additional words that elaborate on it.

Example: "The big, brown dog chased the ball."
The complete subject in this sentence is "The big, brown dog" as it provides a more detailed description of the simple subject "dog."

4. Complete Predicate: The complete predicate includes the simple predicate along with all the words that relate to it and complete the meaning of the sentence. It includes any objects, complements, or modifiers associated with the verb.

Example: "The dog chased the ball in the park."
The complete predicate in this sentence is "chased the ball in the park" because it includes the verb "chased" along with the object "the ball" and the prepositional phrase "in the park."

Remember that the simple subject and simple predicate form the core components of a sentence, while the complete subject and complete predicate provide a more comprehensive understanding of the sentence's structure.