In the process of writing to two people I typed: "Are either of you free?" and was immediately called out by my grammar checker which suggested I should write: "Is either of you free?"
The second of these options feels intuitively wrong to me, as I am addressing two people so should be using the plural. However I feel this is tied up in the whole issue of whether a group should be referred to in the plural or singular sense, e.g.
Red Hot Chili Peppers is a band
Uses "is" to indicate that the band is a singular entity, whereas
Red Hot Chili Peppers are a band
Uses "are" to indicate that the band is made up of multiple people.
So, which is correct? "Is either of you free?" or "Are either of you free?"
Best Answer
Your grammar checker corrected you because "either" does technically function with a singular verb. If you think about your question slightly expanded it would be "is either one of you free?".
However, leaving technical correctness aside, I think conventional usage allows for your question in both forms, and I would ignore your grammar checker if I were you.
By the way this has nothing to do with whether a collective noun (as in your Red Hot Chili Peppers) functions as a singular a plural. That's a separate issue, which I am sure is addressed many times over on this site, e.g. this question