What is it called when you finish a sentence?

There isn't a specific term for "finishing a sentence" in a general sense. However, depending on the context, you could use these terms:

* Ending a sentence: This is the most straightforward way to describe the act of completing a sentence.

* Concluding a sentence: This implies that the sentence has reached a logical end and a complete thought has been expressed.

* Terminating a sentence: This is a more formal way of saying "ending a sentence" and can be used in technical contexts.

If you want to be more specific, you could use terms like "punctuation mark" (period, question mark, exclamation mark), "conjunction" (and, but, or), or "prepositional phrase" to describe the specific element that signals the end of the sentence.