The problem? For the past year and a half I have thought that the Portuguese word for eyeglasses is "o óculos." The first "o" is the masculine singular definite article meaning "the." So, I had thought that even though the word "óculos" appeared to be plural, it should be treated as singular. "Meu óculos" instead of "meus óculos." (You've probably gathered by now that in Portuguese articles and adjectives have to agree in number and gender with the nouns they modify.) I looked it up in my textbook, and sure enough it said "o óculos," just as I've been saying it lo these many months. But when I checked two different dictionaries, they listed the noun as plural. So, was there a typo in my textbook?
No. It's common to hear the noun treated as singular. But technically it is plural. And this is something that baffles Portuguese speakers who are savvy enough to question it. I just consulted an opinion online, and there is a theory that "óculos" has been lumped in with a bunch of nouns that end in "s" but are singular. (My own theory is that, sometime in the history of this word, the phrase "o par de óculos" (pair of glasses) was common, and over time the words "par de" were elided, so that when we say "o óculos, we really mean "o par de óculos"--as in English when we say "a pair of glasses.") Because of this little linguistic anomaly a gringo nearly suffered a stroke last night.
It didn't stop there. I was asking my wife about the phrase "não se preocupe," (don't worry) which I had thought should be rendered "não se preocupa" because it is an -ar verb. We argued back and forth about the correct ending before I realized that in order to form the imperative for an -ar verb, one must use "e." For example, "call me" (by telephone) is usually: "Ligue para mim," with the infinitive being "ligar," an -ar verb. Once we remembered how to form the imperative (and after I sighed relief--I knew I wasn't going crazy, only getting forgetful), we were still confused about the reflexive pronoun "se"--but I won't go into all that.