This study examined three synonymous words (ozzei, ooi, and takusan) in Japanese by classifying modified nouns as human nouns, animal nouns, object nouns, place nouns, or abstract nouns and compared the different roles of the three words as adnominal modifiers.
The summary of the main findings is as follows.
First, the word oozei can only modify human nouns, and, therefore, cannot modify other kinds of noun categories, such as object nouns, place nouns, or abstract nouns. When the word modifies human nouns, the modified noun can be either singular or plural.
Second, the word ooi can modify human nouns, animal nouns, object nouns, place nouns, and abstract nouns. However, there is a constraint on the form of the modified nouns. Whereas both the singular and plural forms of human and place nouns can be modified by ooi, it is only possible to modify the singular forms of animal, object, and abstract nouns with it.
Third, although the word takusan shares many features with ooi as adnominal modifiers, there exists a difference between the two lexical items. As mentioned earlier, the word ooi can modify both singular and plural forms of the place noun. Takusan, however, can only modify the singular form of the place noun. Examples of this, though, are very rare.