Why are plural nouns so complicated? It’s because of Latin.
We don’t tend to think of noun plurals as particularly controversial. One cat, many cats; one participle, many participles. Pretty straightforward. But, as my daughter learned when she was studying for a grammar exam recently, there are many about which reasonable people disagree.
“Your data is all wrong.” That was one of the sentences she had to assess. Is the singular verb all wrong here, too? According to my daughter’s grammar text, it is incorrect. One must say “Your data are all wrong,” since data is the plural form of datum, which meant “something given” in its original Latin and became “a piece of information” in English. One datum, many data – the data all point one way. Except that the data points the opposite way, too. In most disciplines, except for the sciences, data has become a mass noun, a noun denoting something that can’t be counted, like information, gold, or water. It doesn’t make sense to say “he found 20 golds”; you have to say “he found 20 pieces of gold.” (Lucky him!) It’s fine, then, to go with “much of the data is” rather than “many of the data are,” unless you are trying to get published in The Journal of Chemical Physics.
English speakers often run into trouble when grappling with such Latin plurals. Alumnus, for example, is a rare noun that has – mostly – kept its Latin gender inflections in English. An alumnus is a male graduate of a school, or a former member of an organization. An alumna is a female one. Alumnae refers to two or more women, and alumni to a group of mixed gender (whether that’s 10 men and one woman, or 1,000 women and one man).
Problems arise either when we just don’t remember these forms, or when we search for a gender-neutral word. Many universities try to avoid “official” speech that might marginalize women – the “freshman class” becomes “the frosh” or “the first years.” They want a word that signals “I graduated from this school,” not “I am a person of a particular sex who graduated from this school.” Unfortunately, the word often chosen is alumni. When I see a car window sticker that boasts “UW alumni,” I always wonder if the vehicle belongs to a couple who met at college. Even odder are T-shirts printed with “Paul Smith College alumni.” Are these shirt-wearers making a statement about “containing multitudes” like Walt Whitman, or is alumni just being used incorrectly? Perhaps, more charitably, it is a nod to the whole group of alumni, to which the shirt-wearer belongs. In any case, it is confusing and leads to people saying things like “I am an alumni of Georgetown.”
Luckily there already is a perfectly good gender-neutral alternative, which has been used since the 19th century: one alum, two or more alums.