When is it inappropriate to use the pluralizing suffixes -たち, -ら?


In _" A Dictionary of Advanced Japanese Grammar"_, it says that there are
cases where _-tachi_ cannot be attached to a noun, as in:

> a. 川本と柴田は大学の教師(*たち)だ。(Kawamoto and Shibata are college professors.)
>
> b. 彼には子供(*たち)がある。(He has a child/children.)

"Except in the above cases, the attachment of the suffix _-tachi_ is
optional."

I assume that the use of _-tachi_ in (a) is improper because the plural is
evident as is, but why is (b) the case? Is there a nuance to Japanese
pluralizing suffixes apart from just making a noun explicitly plural?




I think the reason たち cannot be used in those sentences is that the words
before it don’t refer to concrete people.

> 川本と柴田は大学の教師だ。  
>  Kawamoto and Shibata are college professors.

川本 and 柴田 are concrete people, of course, but 教師 refers to their status, not
Kawamoto and Shibata themselves. It is an abstract concept.

> 彼には子供がある。  
>  He has a child/children.

子供 in this sentence is also an abstract concept that refers to someone to whom
you are a parent, not any concrete child or children.

The following sentence gets a different meaning.

> 彼には子供たちがいる。  
>  He has his children (to take care of, count on, etc.).

子供たち here is understood as referring to his own children, or children under
his care.

This concreteness becomes more obvious when たち follows a proper name.

> 太郎たちはまだ来ていない。  
>  Taro and others haven’t come yet.

In this case, たち plays a similar function to “et al.”

Maybe you should stop seeing it as a “pluralizing suffix” and start seeing it
as a marker that extends what it marks (e.g. 子供) into a larger group of people
that includes it.




I think the reason たち cannot be used in those sentences is that the words
before it don’t refer to concrete people.

> 川本と柴田は大学の教師だ。  
>  Kawamoto and Shibata are college professors.

川本 and 柴田 are concrete people, of course, but 教師 refers to their status, not
Kawamoto and Shibata themselves. It is an abstract concept.

> 彼には子供がある。  
>  He has a child/children.

子供 in this sentence is also an abstract concept that refers to someone to whom
you are a parent, not any concrete child or children.

The following sentence gets a different meaning.

> 彼には子供たちがいる。  
>  He has his children (to take care of, count on, etc.).

子供たち here is understood as referring to his own children, or children under
his care.

This concreteness becomes more obvious when たち follows a proper name.

> 太郎たちはまだ来ていない。  
>  Taro and others haven’t come yet.

In this case, たち plays a similar function to “et al.”

Maybe you should stop seeing it as a “pluralizing suffix” and start seeing it
as a marker that extends what it marks (e.g. 子供) into a larger group of people
that includes it.

