In German:
die See (female) means: the sea (as in: the North Sea = die Nordsee)
der See (male) means: lake
That would probably be true of a speaker of almost any language having a well developed grammatical gender system, since the endings of words tend to correlate with specific genders. (E.g. Latin -us is usually masculine; Greek -η is usually feminine, etc.)
As far as clarifying meanings, I can think of one example from the Cree language: mistikw means either “tree” or “stick” depending on whether it is animate or inanimate.
French doesn’t have anything as obvious as the Latin “-us, -a, -um” gendered endings, though.
I don’t know to which writer you refer but he certainly did not invent school for a group of fish. School is simply an altered form of shoal and has nothing to do with the other school.
I think you’re wrong about most of these. “Swarm” has been in use to describe groups of flying insects since the 8th century and “school” for fish since about the 14th. “Pack” isn’t attested for use with dogs and wolves until the 17th. The OED gives no examples of “superfluity” as a collective noun for nuns before 1909. I’ve never heard of a “fighting” of thieves; might you be thinking of beggars instead? That one (and “gaggle” for geese) do both come from these apocryphal medieval lists. Also never heard of a “glaring” of cats.
Maybe not as obvious by a matter of degree. But if I offer “chaton” or “chatonne” to someone who isn’t familiar with either word but is familiar with the basics of French grammar, they would instinctively (and correctly) assume “le” for the former or “la” for the latter.
In Germany, ever creeping political correctness requires to use the female version as well as the male version whereas in the olden days, the male version stood for both, hence:
*Studentinnen und Studenten *
(female) students and (male) students
Politikerinnen und Politiker
(female) politicians and (male) politicians
Sometimes, maybe as a gesture of atonement for centuries of male oppression, only the female version is used:
Unternehmerinnen
(female) entrepreneurs
For some unknown reason, the female version is almost never used in these cases:
Mörderin
(female) murderer
Dikatorin
(female) dictator
Betrügerin
(female) cheater
Kannibalin
(female) cannibal
Ausbeuterin
(female) exploiter
Though I have no source to back me up, I have no reason to doubt that the source of grammatical gender is the same as, for example, the four humors, the four elements, the yin and the yang, etc. People just like to make (often) arbitrary distinctions between things, for the sake of magic, mysticism, and divination. I’m sure that, through the ages, the male/femaleness of words has provided ample fodder for many mystics as they tell your fortune. “Oh you have too many words in your life that are feminine! You need to balance with other things that have masculine names!”
But that’s (probably) all there is to it.
How difficult is it to explain to a native speaker of a language with no articles (e.g. Chinese) the difference between ‘a person’ and ‘the person’ ?
Actually, “shoal” of fish is exactly what she said. I wrote “school,” because it turned into that, albeit, I know some people who still say shoal.
As for “swarm,” I did say I wasn’t sure about some of them-- which were invented and which weren’t.
I’ve never tried, but I had to accomplish similar things learning Japanese.
Japanese has kore, sore, and are, as well as kono, sono, and ano which all reference something in my region, something in your region, or something away from both of us. There is no equivalent concept in English.
It’s not too hard to wrap your head around.
I want “a” pencil. -> I don’t care which one. I just want one.
I want “the” pencil. -> I want a specific pencil, and you should be able to tell which one by context.
Japanese does allow one to say, “rei no penshiru”, where the “rei no” serves a similar purpose as “the” but it’s rarely used. I wouldn’t be surprised if Chinese has something similar.
Similarly, Japanese lacks plurals, so if you want to indicate that there are more than one, you have to add extra words to your sentence, saying things like, “I want all of the pencil” Or, “Get the pencil, no matter how many.” Or, “I want the plural pencil.” Again, presumably, there are similar ways to accomplish this in Chinese.
It’s generally harder to gain an appreciation for things that don’t exist in your language than it is to drop things. E.g., it’s probably easy to forgo masculine and feminine, while it’s hard to pick them up. Dropping things is actually pretty easy, up to the point where you are in a position where you actually need to add that extra information, which is so easy to impart in your home language, and suddenly find that there’s no straightforward way to do it.
Hard. It’s even harder to explain to someone whose language depends on context to pluralize words how to pluralize compound nouns. I babysat for a Chinese family-- the parents came here as adults-- and they could never get “chocolate chip cookies” right. It was always “chocolate chips cookie,” which I understood the thinking behind. Deaf people have a hard time with both plurals and prepositions, because American Sign Language handles them both very differently.
As you described them, Kore, sore, are, kono, sono and ano are sort of like English this, that, yonder, these, those, any. Too bad yonder isn’t used anymore, it was useful.
I am not a native speaker of a gendered language but when I see a native speaker of French or Arabic hear someone make that mistake, the reaction is usually amusement. Imagine someone using the wrong gender in English about a person. “My father was here, but now she’s gone.” That’s as close an analogy as I can suggest.
Sort of. “That” has more meanings than simply “by you”. Like, “I saw that dog again.” In Japanese, it would be ano, “I saw ano dog again.” Since the dog is not near either of us.
Or something like a non-English speaker who mixes up a/an. I want a apple. There is an house here.
On the one hand, it’s not a barrier to understanding, on the other hand, it is clearly an error.
Hungarian has no gender of this sort. My parents, whose native language is Hungarian, make this kind of error all the time. They are constantly mixing up “he” and “she”, which sounds very peculiar to English speakers.
Maybe that’s why most French men don’t wear full beards 
As a native German speaker, I agree with this. I’ve heard from other gendered-language speakers that it is odd to stop and actually think what words receive what gender.
It is helpful to remember that grammars don’t evolve based on practicality or logic, and hence aspects of a language’s system may stick around for no good reason at all. Perhaps very early protolanguages found it more expedient to transfer gendered pronouns from “man” and “woman” - certainly central nouns in any early language or communication system - to whatever else happens to crowd the landscape?
Good point. In English one such cookie should be a chocolate chips cookie. After all, it contains many chocolate chips. If it did have only one chip it’d be real defective.
So several such cookies ought to be chocolate chips cookies.
Along a different line I was writing something in Elections the other day and referenced Bill Clinton the former President and also other folks who happened to share his name. Are they collectively Bill Clintons or Bills Clinton?
Bush Senior & Junior are Presidents Bush. If HRC wins she and Bill will be Presidents Clinton.