I had a student this semester use this word: ignologe. It took my colleagues only a few seconds to figure it out, but it took me nearly a half hour (I graded other papers while this "word" bounced around in my subconscious
That one I got quickly, and I think it's not too far off from how people often pronounce it.
It DOES tell us that they aren't hearing words correctly. That's why they so often confuse whether and weather, quiet and quite, and even then and than. When I talk to them about it in class, they really can't hear the difference. I have no clue as to why.
Some of this may be dialectical, and some of may just be laziness in speech. I'd guess that it's not usually primarily a listening issue, per se, but rather an issue of the speech people receive. Unless I'm consciously affecting my speech (and I mean "affecting" in the sense of putting on airs or enunciating in a way that is very unnatural to me), I pronounce "whether" and "weather" the same way (and that goes for most words with "wh" - "whale" = "wale", "what" = "wut", "where" = "wear", etc.). Depending on context, "then" and "than" may or may not sound the same. I'd say "than", as in "Better Than Ezra" (a band from the '90s, maybe?) or with a schwa tending towards a short "e" in the middle - definitely not a short "a". "Faster than a speeding bullet" and "more powerful than a locomotive" may come a little closer to short "a", but that may be the influence of the TV show announcer, with his mid-century TV announcer dialect.
I also pronounce the number "20" as "twunny" (short "u" tending towards "e"), not "twenty".
Clearly, the only logical conlusion is that it's
my fault your students can't spell! ;)
(Except for quite and quiet. Those I always distinguish.)
And I think I've posted this one before, but I once had a student write a paper about the tragic deaths of the ocra pups at the local zoo. Ocra should not be raised in captivity, she explained, but baby ocras should always be allowed to swim free in the ocean with their mothers.
That's a funny example. I hear orkas are soggy and/or stringy unless cooked properly.
I heard, and this may or may not be apocryphal, that Oprah's mother intended to name her after a biblical figure (Orpah) but did the same thing your student did and transposed the sounds and letters.
Edit: I agree with finallydone, though, that lack of exposure to the written forms of many of these words may also play a major role. I'll admit that for years I thought the word "Chaos" rhymed with "Taos" and had a "ch" as in "Chuck"; there was a video game called "Dr. Chaos", and I thought it was just his name. Meanwhile, I knew the word "chaos" well aurally, and probably used it, but had never thought about how to spell it. And then I was surprised and excited to learn they were one and the same. Ditto on the name "Chaim", as in Potok. Like "chain", but with an "m" at the end, right? :)
Edit: If you are pronouncing them in class and they still can't hear the difference, then maybe there is a listening component as well. I'm curious whether (weather?) you are teaching in the region of the country where you were raised, or in a different region. (This shouldn't make a difference if you are enunciating the different sounds, but it may affect whether the local dialect has the same quirks as yours.)