Plurals and Singulars

The verb-to-noun agreement generally involves a problem of using is or are as a principle verb, but it is easily remedied by (1) subordinating is or are to another verb, (2) substituting by a stronger verb, or (3) changing the number (singular or plural) of one of the elements.

Incorrect

Deltaic strata are the chief petroleum reservoir.
The red beds of the Catskill formation are a counterpart of the Old Red Sandstone.
The Wasatch Mountains are a narrow upfaulted range.

Correct

Deltaic strata compose the chief petroleum reservoir.
The red beds of the Catskill formation are counterparts of the Old Red Sandstone.
The Wasatch Mountains form a narrow upfaulted range.

Branches of knowledge like geophysics, mathematics, ethics, politics, tectonics, etc. are singular.

Statistics meaning simply “figures” is plural; so too is economics in the sense of “commercial viability”, as in the economics of the new process were studied in depth.

A few words, though singular in nature, are made of paired items and generally treated as plural: scissors, trousers, glasses, pliers, tongs, and the like. Many are often used with the word pair as in pair of trousers or pair of scissors.

Titles of books and other works of art are always considered singular even if the title sounds plural.

The Alfred Hitchcock film The Birds was successfully advertised with a campaign that said, " The Birds is coming!"