A sentence is a group of words that contains a subject and a predicate and expresses a complete thought. A clause is a group of words that contains a subject and a predicate but that may not express a complete thought.
Subject is the word or words naming the person, place, or thing about which something is said.
Predicate is the word or words telling something about what the subject is or does.
A brief summary of the four types of sentences is included here to provide a frame of reference for your study of sentence structure:
1.Smple Sentence. A simple sentence contains only one clause. The subject or predicate may be compound (a compound subject contains two or more nouns, and a compound predicate contains two or more verbs)
Ted handed the fuse to his assistant.
Mary and John often sing and dance at the company party.
2.Compound Sentence. A compound sentence consists of two or more main clauses.
Main clause is a clause which makes a complete statement and may stand alone is a sentence.
One of the drivers delivered the order of tires, and the other driver picked up a special set of jacks for the truck.
Note: Don't confuse a true compound sentence with a simple sentence having a compound predicate.
The construction workers were met at the bus station and driven to the site of the new stadium.
3. Complex sentence. A complex sentence contains one main clause and one or more dependent clauses. A dependent clause is sometimes called a subordinate clause.