2.6. The category of number (singular and plural) is more familiar to us—and Greek number is very much like English number. The most common way to indicate number in English is to add the letter s to a noun to make it plural (dog ► dogs), but there are other ways to indicate the difference in number: child ► children; ox ► oxen; mouse ► mice. Sometimes the same word is used to indicate both singular and plural: sheep. 2.7. Case identifies the function of a noun or pronoun in a sentence.
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