How do I format a short quotation?

A direct quotation reproduces the words of another writer word for word.  A short quotation is under four lines long, it should be incorporated into the text and enclosed using quotation marks. You may include the author’s name within your text or within the in-text citation.

One work by one author

According to Badke, "Many faculty members view writing as a significant issue for undergraduate and graduate students" (2).

OR

"Many faculty members view writing as a significant issue for undergraduate and graduate students" (Badke 2).

One work by two authors

Clarke and Oppenheim state that “Citations to electronic materials have been found to increase over time and the use of hardcopy materials has substantially decreased ” (24).

OR

“Citations to electronic materials have been found to increase over time and the use of hardcopy materials has substantially decreased” (Clarke and Oppenheim 24).

One work by three or more authors: provide the first author's last name, followed by et al.  Et al. is an abbreviation of the Latin phrase et alia, which means "and others."

Duff et al. state that "The reasons for plagiarism are as vast as its instances" (680).

OR

"The reasons for plagiarism are as vast as its instances" (Duff et al. 680).

How do I format a long quotation?

For quotations that are more than four lines of prose or three lines of verse, place quotations in a free-standing block of text and omit quotation marks. Start the quotation on a new line, with the entire quote indented half an inch from the left margin; maintain double-spacing.

Nelly Dean treats Heathcliff poorly and dehumanizes him throughout her narration: 

They entirely refused to have it in bed with them, or even in their room, and I had no more sense, so, I put it on the landing of the stairs, hoping it would be gone on the morrow. By chance, or else attracted by hearing his voice, it crept to Mr. Earnshaw's door, and there he found it on quitting his chamber. Inquiries were made as to how it got there; I was obliged to confess, and in recompense for my cowardice and inhumanity was sent out of the house. (Bronte 78)