Subject and Predicate

A sentence is group of words which expresses a complete thought
   i.e. He ate an apple.

A sentence consists of two parts i.e. subject and predicate.
Sentence = Subject + Predicate

Subject

The part of sentence which performs some action in a sentence is called Subject. A subject is sometimes also defined as the part of sentence which is being spoken about in sentence (especially in sentences having a static verb). A subject has a close relationship to what is being discussed in sentence. A subject can be a noun, pronoun, noun clause or noun phrase.

Examples
           He is flying a kite.
           John is driving a car.
           She ate an apple
           I wrote him a letter.

Predicate

The part of sentence which tells about the subject is called predicate.
Examples
         He is flying a kite.
         John is driving a car.
         She ate an apple
         I wrote him a letter.
       Subject refers to the actor of a sentence. The part of a sentence about which something is told in a sentence is the subject of sentence. While the part of a sentence that tells something about subject is the predicate of sentence.
Example.

                  
In the above example, “she” is a subject because it performs an action of washing clothes. We can also say that “she” is a subject because something (that she is washing her clothes) is told about it in sentence. While the rest part of the sentence “is washing her clothes” is predicate of sentence because it tells something (washing her clothes) about the subject.  

Related Topics:

	Sentence
	Kinds of Sentences        (According to function)