In Mandarin, every countable noun (that is, every noun you can count—unlike snow or water, for example) has a special measure word associated with it. It’s like in English when you say “grains of sand” or “sheets of paper.” So, whenever you talk about a certain number of a thing, you have to know the correct measure word. This presents another challenge for Mandarin learners: along with learning a new vocabulary word, you also have to learn a counter word. Fortunately, however, there is some order to the chaos. For instance, long, skinny objects tend to use one counter word. Clothing worn on the bottom half of your body gets one counter word, while clothing on the top half gets another. Knowing rules like these, you can make some categorizations to help with the learning process.
In Mandarin, there’s also a general counter word that you could theoretically use to stand in for any counter word and be understood (especially if your tones are perfect and your grammar is otherwise acceptable). It’s a temptation for some learners to use only this word for all their counting purposes. To me, and to many Chinese people, this takes a lot of delightful nuance and complexity out of the language. So, I’ve been studiously memorizing the corresponding counter words for many of the nouns I learn.
I’d like to thank the content developers at Rosetta Stone, my former employer, for including the correct counter words in the Mandarin product. I’m able to pull the counter words out of my head without too much trouble, especially compared to some of my classmates who haven’t used Rosetta Stone. Having heard the counter words in tandem with the nouns, I find that I have the sound of them in my head. Later, I seem to intuitively know the correct counter word, sometimes to the mystification of tutors and teachers. So, thank you, Rosetta Stone, for choosing the more difficult, but more correct route!