Here's why:
* Subject: The subject of a sentence is the person, place, or thing that performs the action.
* Verb: The verb describes the action or state of being of the subject.
A single sentence needs one subject and one verb to be grammatically complete.
However, you can combine multiple independent clauses using conjunctions like "and", "but", or "or" to create a compound sentence. Each independent clause in a compound sentence has its own subject and verb.
Example:
* Simple Sentence: The dog barked. (One subject "dog" and one verb "barked")
* Compound Sentence: The dog barked, and the cat meowed. (Two subjects "dog" and "cat", and two verbs "barked" and "meowed")
Let me know if you'd like more examples!