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Q. A colleague writes: “Basement space is about 5,700 square feet, but about 12,000 square feet is available on the eighth floor.” I suspect the point is arguable, but couldn’t that be “12,000 square feet are available on the eighth floor”?
A. Although it might seem counterintuitive, quantities of weight or measure are considered singular: five dollars is enough; three cups of flour makes one loaf. When you think about it, “12,000 square feet are available” reads as though someone short of cash could buy just one or two of them.