How should I style ellipses in MLA style?
The MLA Handbook explains that you should “[i]dentify an omission within a sentence by using three periods with a space before each and a space after the last ( . . . )” (81). Note, however, that if you use Microsoft Word’s ellipsis character, the periods will not be spaced, and if you try to insert three periods with spaces, Word will change them to an ellipsis without spaces. To turn off that feature, go to File, then Options, then Proofing, then click the AutoCorrect Options button. Select the AutoCorrect tab. You can then uncheck the “Replace text as you type” box, or simply delete the ellipsis character from the list.
MLA Handbook. 8th ed., Modern Language Association of America, 2016.