In English we express number as singular (one) and plural (more than one). Navajo, on the other hand, expresses number as singulra (one), dual (two), duoplural (two or more), plural (more than two), and distributive plural (indicating not only that the number is more than two, but also that each of the subjects or objects in reference is taking part in the act, state or condition denoted by the verb). To illustrate with concrete examples:

yishááł I am walking along
yiit'ash we two are walking along
yiikah we (plural) are walking along
niheezná they (duoplural) moved with their goods
ndahaazná they (distributive plural) moved with their goods

The distributive plural is indicated by the prefix da-. It is used regularly with verbs, and on occasion with nouns. In the latter case it indicates that there are many individually scattered about, and the attention is focused on themas individuals rather than in collectivity. Thus kǫ' (fire) and daakǫ' (many fires). Chóshk'eh (dry wash) chádaashk'eh (dry washes).

A few personal nouns such as boy, girl, youth, maiden, etc. as well as nouns which express genealogical relaitonship are rendered plural by suffixation of -ké or -(y)óó. Thus: 'ashkii (boy) 'asiiké (boys); 'at'ééd (girl), 'at'ééké (girls); sik'is (my sibling -- of same sex as self), sik'isóó (my siblings).