Which is correct?
Because black absorbs light (which equates to heat) and white reflects it, white is a better option for data center _____.
Answer: Either, depending on where you are.
In the U.S., roofs is the standard plural of roof; elsewhere rooves is fairly common but becoming less so. The same holds true for an increasing number of words ending in “f.”
The standard/traditional rule for words ending in “f” – the one I grew up with, of course — is that we substitute a “v” for the “f” and add “es” to form the plural:
The rule on “roofs” has changed so completely in the U.S. that Merriam-Webster no longer even has an entry for “rooves.” Although the standard rule for most words ending in “f” still holds, in casual speech and writing words like “calfs,” “elfs” and “loafs” are appearing more and more. What that means, in all likelihood, is that more will follow and the old rule will change, so that words ending in “f” just take an “s” for pluralization, like most words ending in a consonant.
And there’s nothing wrong with that, other than that in the transitional period, people who say “calfs,” “elfs” and “loafs” may be ridiculed by those of us clinging to the old rule. That being the case, stick to the standard for formal writing.
Writers on the Net provides resources on irregular plurals.
A tip of the editor’s visor to @Guy_in_PEI for the inspiration for this post. (What, no one’s wearing those green eyeshades any more? Oh, I AM behind the times.)
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