Translation:They are not students.
Wouldn't "Those guys aren't students." Be acceptable? Like "她们不是学生" would be "Those girls aren't students."
Exactly... You can not know it is meant as men unless you see it written or hear the whole concept imo.
The audio-to-text version of this question should also accept the female they, since they're pronounced the same, right?
I don't understand "不是" as meaning "not". Can someone please explain? I thought just "不" meant 'not". What is the meaning/value/use of "是"?
I think 是 is kind of like an 'are'. So without the 是, i.e. 他们不学生 roughly translates to 'They not students', instead of 'They are not students'.
是 means more of like "are" in this case. Just like you would say 不要 to say "dont want" 不是 in this case would mean more along the lines of "they 'are' not students" . 不 is almost always paired with another word and acts almost like a negative prefix. The opposite of this sentence would be 他们是学生 (they are students), so it makes sense that just adding the 不 would change the meaning to mean the opposite.
Is "们" always used for plurals? Are there other characters which can also be used to make nouns plural?
Unless im mistaken, 们 is saved just for plurals of human nouns (我们，你们，学生们，同学们，etc.) You wouldnt say 毛们 or 桌子们. You can tell by the 人 radical that its meant to be for humans. Chinese dont really have plural versions or suffixes of words, we just say the number. For example: 两个毛，五个桌子
That's the right concept. Take note that the correct way to say it would be 两根毛 and the more accurate way of describing it would be 两张桌子.
个 is a pretty useful 量词 but it isn't universally applicable, nor is it always the most accurate.