It is often difficult for learners of English to know whether to use "-s" or "of", as in expressions like this:
our team's victory vs. the victory of our team.
There is a lot of overlap between these two expressions, but in this Column and the one following this (Column 130) I will present the main rules.
To start with, there is a very general rule to the effect that when the "possessor" is a human being, we use "-s":
1) Mary's pen
2) the girl's toy
A further rule is that the closer the possessor is to being a human being, the more likely "-s" will be used.
For example, when "Japan" is seen as "an area or land", we would use "of", as in the following:
3) a map of Japan
4) the mountains of Japan
However, when "Japan" is seen as "a group of human beings / a society" we are more likely to use "-s", as in the following:
5) Japan's aid to foreign countries 日本の海外援助
6) Japan's hosting of a marathon 日本によるマラソンの主催（日本主催のマラソン）
In the following examples, we can use either "-s" or "of". As can be seen from the examples, these are borderline cases, in which "Japan" is perhaps an area, or perhaps a group of human beings:
7) Japan's economy ＞ of
8) Japan's ancient customs ＞ of
9) Japan's transport network ＞ of 日本の交通網
10) Japan's constitution ＞ of 日本の憲法
In the next Column I will give a list of types of nouns which use "-s" in the possessive.
To start with：まず第一に
to the effect that ...：...という趣旨の
a borderline case：どっちつかずの状態、中間的な場合
the closer the possessor is to being a human being：所有者が人間に近ければ近いほど＜the possessor is closer to being a human being（「the -er ..., the -er ～：...すればするほど、それだけ～」のパターン）
be seen as ～：～と見なされる
either A or B：AもBも
As can be seen from ～：～からわかるように