量词 liàngcí "measure word"
Finally, Chinese nouns require classifiers (also termed measure words) in order to be counted. That is, when specifying the amount of a countable noun, the classifier has to agree with the noun. Hence one must say "兩頭牛/两头牛 two head of cattle", not two cows, with "頭/头 head" being the unit of measurement, or measure word. This phenomenon is common in East Asian languages. (In English, some words, as in the cited example of "cattle", are often paired with a noun used much like the Chinese measure word. Bottle in "two bottles of wine" or piece in "three pieces of paper" are examples; one does not typically say, "two wines" or "three papers", unless talking about types of wine or academic research, respectively.)
Classifiers are generally associated with certain groups of nouns related by meaning, such as "條/条 tiáo" for long, thin objects or animals (e.g. ropes, snakes or fish), "把 bǎ" for objects with handles (e.g. knives, umbrellas) "張/张 zhāng" for flat objects that can be counted as sheets in English (photographs, fur, etc.). While there are dozens, if not hundreds, of classifiers that exist, which must be memorized individually for each noun, the vast majority of words generally use "個/个 gè". Many nouns that may use other classifiers can also use "個/个" if the speaker chooses. The classifiers for many nouns appear arbitrary. "Table" (桌子 zhuōzi) is a "zhāng 張/张" noun probably because table-top is sheet-like and "chair" (椅子 yĭzi) is a bǎ noun probably we move a chair by lifting a "handle," while another word for chair or stool, "凳子 dèngzi" is a "個/个 gè" noun.
The endings for the indefinite and demonstrative article must also agree with the appropriate classifier for a noun. For example, "狗 gǒu" means "dog" or "the dog." But to specify "that / that (in direction of addressee) / this dog" (demonstrative) one says "那只狗/这只狗 nèizhī / nàzhī / zhèizhī gǒu," and to say "a dog" one says "一只狗 yìzhī gǒu," where the ending "只 -zhī" agrees with the classifier of the noun "狗 gǒu." Similarly, "that / that (in direction of addressee) / this / a house" are "那座房子/这座房子/一座房子 nèizuò / nàzuò / zhèzuò / yízuò fángzi," where the ending "座 -zuò" agrees with the noun "房子 fángzi."
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