Punctuation and capitalization

The ellipsis is "a mark (as ...) indicating an omission (as of words) or a pause" (Merriam-Webster, n.d., 2). The most common usage of the ellipsis in North American Academic English is to indicate where words have been left out of the middle of a quotation. For example, “omission ... or a pause”. The APA style rules discourage authors from using an ellipsis at the beginning or end of a quotation (American Psychological Association, 2020, p. 275). Rather, begin the quotation at the text that is relevant to your study, and similarly, close the quotation at the completion of the relevant text. The only exception to this approach is if omitting the ellipses at the beginning or end of a quotation could lead to misinterpretation of the quotation (p. 275). To format an ellipsis, 

Type three periods with spaces around each ( . . . ) or use the ellipsis character created by your word-processing program when you type three periods in a row ( ... ), with a space before and after. ...Use four periods—that is, a period plus an ellipsis (. ...)—to show a sentence break within omitted material, such as when a quotation includes the end of one sentence and the beginning of another sentence (p. 275)

The ellipsis is also sometimes used to indicate, "the omission of one or more words that are obviously understood but that must be supplied to make a construction grammatically complete" (Merriam-Webster, n.d., 1a). For example, “I'm thinking of going out for brunch on Sunday ... see you there?”

References

American Psychological Association. (2020). Publication manual of the American Psychological Association (7th ed.). https://doi.org/10.1037/0000165-000

Merriam-Webster. (n.d.). Ellipsis. Merriam-Webster's online dictionary. Retrieved September 4, 2020 from http://www.merriam-webster.com/dictionary/ellipsis