Which is correct?
______________ computers both really need to be defragged.
a. Bill and my
b. Bill’s and my
c. Mine and Bill’s
To see that c. is wrong, just do the old trick of taking Bill out of the equation. “Mine computer really needs to be defragged” sounds a trifle affected, don’t you think?
Amd, assuming that Bill doesn’t need to be defragged, a. is also the wrong choice. (Bill may, of course — God knows I could stand a good defragging some days.) But if you mean that Bill’s computer and your computer both need to be defragged, pick b.
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