Singular or plural verb after units of measure [duplicate]

Should the verb in the following sentences be singular or plural?

• Two cups of sugar [was or were] added to the recipe.

• Fifty cubic yards of contaminated soil [was or were] excavated.

Solution 1:

Typically, with units of measure, one uses a singular verb. For example, if you are most interested in a single quantity of sugar, that happens to be two cups, you would say two cups of sugar was added to the recipe. In fact, it might have been half of a 1-quart measure, or it might have been four half-cup measures.

Almost certainly, you are uninterested in whether the fifty cubic yards of earth was added in fifty increments or otherwise.

See, for example https://www.aje.com/en/author-resources/articles/editing-tip-singular-and-plural-verbs-measured-quantities.

Consider also the following sentences:

*Two cups are too much sugar for that recipe!

Two cups is too much sugar for that recipe!

*Fifty cubic yards were a lot more contaminated soil than we anticipated.

Fifty cubic yards was a lot more contaminated soil than we anticipated.

As an aside, you can avoid this by using the active voice, which many style guides prefer when a choice is possible:

The baker added two cups of sugar to the recipe.

The contractor excavated 50 cubic yards of soil.