Punctuation refers to the marks used in writing that help clarify meaning and separate linguistic units. Examples include periods, commas, question marks, and exclamation points.

The subject is the part of a sentence that tells who or what the sentence is about. It usually includes a noun or pronoun.

A verb is a word that describes an action, occurrence, or state of being. Examples include 'run', 'is', and 'think'.

A complete sentence must have a subject and a verb and express a complete thought. For example, 'The dog barks.'

A comma is used to indicate a pause between parts of a sentence, to separate items in a list, or to set off clauses.

A question mark is used at the end of a sentence to indicate that it is a question.

Incorrect punctuation occurs when punctuation marks are used improperly, leading to confusion or misinterpretation of the sentence.

A compound sentence is made up of two or more independent clauses joined by a conjunction. For example, 'I wanted to go for a walk, but it started to rain.'

An exclamation point is used at the end of a sentence to express strong emotion or emphasis.

A run-on sentence occurs when two or more independent clauses are joined without proper punctuation or conjunctions.