Not at all. In my hometown (Hue City), "ca" is used a lot in everyday conversations. It's equivalent to both a cup/glass and a plastic pitcher.
I'm living in HCM City now. It seems that "ca" is just equivalent to a plastic pitcher in Southern dialects. For cup/glass, people prefer using "ly". So if you come to a food/water stall here and order một ca nước (a pitcher of water) and một ly nước (a glass of water), they will give you two different things.
I don't have information about the use of ca in Northern dialects. Maybe it isn't common any more in these dialects.
In the Southern part of Vietnam (at least from South Eastern region and down under), most of us would use "ca" for "pitchers/jugs" which hold a much larger volume of liquid than "ly" ("glasses/cups/mugs"). People in the North would properly use "cốc" which is the equivalent of "ly". So I suggest that "ca" should be replaced by "ly/cốc" if you want to mean "a mug".
I would use "cốc" for the North: "một cốc cà phê" and "ly" for the South: "một ly cà phê". (note that: "ly" means "glass" in the North, "một ly rượu"-"a glass of wine")
Cái is a classifier or a measure word. Cái typically refers to one unit of an inanimate object. Note that there are other classifiers in Vietnamese as well. Classifiers are seldom used in English but do exist.
For example, in English we say:
- "# sheet(s) of paper" instead of "# paper(s)"
- "# ear(s) of corn" instead of "# corn(s)"
So, I guess the best approximation here would be "one [thing of] mug".
Man the accent is weird. Sounded like mộn. Ca is not common either... I'm with le_nhat on this for vernacular used in major cities. Hanoians will naturally claim theirs is the right version though haha.
Wonderful point, though I would point out that "notice" is what the student does, while what you did was "point out" in the tips and notes. And thank you very much for your effort in doing so.
Do we always need to use the classifier? It seems as though "Một ca" would get the idea across. Is it just that we always need some sort of classifier before a noun?
When you use number before a noun, yes, you need a classifier. But in some other cases, you don't always need classifier. For example: "Tôi có một cái ca"-"I have a mug". But: "Tôi không uống nước bằng ca"-"I don't drink water with a mug"
other option should be available since the south calls a mug or glass "ly" so.. I wonder what dialect the mod are using.
so it's like mandarin? ''wo you si pan dangao'' (i have four plates of cake) or wo you yi bei kafe? (i have a cup of coffe) or ta de jia you si ge ren? (his family has four people) or liang ge meiguo ren? (two american's)
Được cái card rồi tôi đốm bạn Tuyết cái card có nghĩa là gì làm mất đấy ahihi