A subject of a sentence is the person or thing that is performing the action of the verb. In order to find the subject of a sentence locate the verb and ask yourself who? or what? is doing the action of the verb. We can use this strategy in an example:

• The dog swims across the lake. (The verb is swims so we ask, “Who swims?” or “What swims?” The answer is the dog.) 

Subject pronouns are pronouns that replace a noun previously mentioned. They act as the subject of the sentence. Here are the English subject pronouns:

• singular subject pronouns: I, you, he, she, and it.
• plural subject pronouns: we, you, and they. 

Here is are some examples. Notice how the subject pronouns in the second sentences replace the subjects in the first. 

• The black dogs get hot in the sun. They look for the shadiest spot in the yard to rest.
• “When did Tara leave for Turkey?” “She left yesterday morning.”
• Scott and I went to the store and ran some errands. Now we are ready to host the party.