Find the complete subject and the simple subject in the sentence.

The weather has been extremely hot this summer.

The complete subject is "the weather" and the simple subject is "weather"

Explanation:

Simple subject definition: A simple subject is a main word or words that tell what or whom a sentence discusses, not including any modifiers.

Complete subject definition: A complete subject is all of the words that tell what or whom a sentence discusses, including any modifiers.