The ... in a sentence is called an ellipsis (plural ellipses).
It is used to indicate words left out.
Examples:
Lincoln said, "Four score and seven years ago...". The ellipsis indicates that he said more than what I've quoted.
In the next scene he says "...what sounded like a countdown...". In this example, the ellipses show that I have taken a statement from the middle of a quote.
You will see many misuses of ellipsis, such as this answer from another question:
"Yes... you should definitely tell them because it could harm them and maybe even others..."
This was exactly how the answer was written. Many people use ellipses to form sentences instead of using capitalization and correct punctuation. Please don't use ellipses like this.
A subject in a sentence is who, what, or where the sentence is about.
This is a sentence. A prisoner has to serve the sentence the judge gives him.
This example sentence uses the word 'sentence' in an exemplary fashion.
a good sentence is "I cannot use oversimplification in a sentence." that sentence is oversimplification.
a sentence that tells a fact is a declarative sentence
It in symmetry with sentence a is what? What is a sentence with symmetry in it? This sentence with symmetry is symmetry with sentence this.
It is the first sentence of a paragraph which is the topic sentence.
Who or what the sentence is about is the subject of the sentence.
Who or what the sentence is about is the subject of the sentence.
The subject of a sentence is who or what that sentence is about.
yes
the meaning of sentence is sentence
A subject in a sentence is who, what, or where the sentence is about.
As a question, it can be a sentence, like: A sentence can have one word, and as a question then it can be a sentence: Who?
compound sentence, simple sentence, and complex sentence
a descriptive sentence is a sentence that describes something in one sentence
This is a sentence. A prisoner has to serve the sentence the judge gives him.