The next basic structure you should understand is the の phrase structure. This type of phrase will allow you to make nouns possessive in Japanese. This structure involves three main components: the main topic, the modifier, and the particle の. The particle の often acts as an apostrophe, but it is also used to connect two nouns.

The basic structure is: nounのnoun. In terms of modifier and main topic, the phrase looks like this: modifierのmain topic. Look at the examples below.

だいがくのせんせい            daigaku no sensei                               a college professor

わたしのいぬ                        watashi no inu                                     my dog

これはわたしのほんです。Kore wa watashi no hon desu.            This is my book.

In the first example, の is used to connect two nouns in order to modify the main topic. For example, you could say せんせいです(I am a teacher). If you wanted to elaborate on that and say you were a college professor, you can use のto add the extra information. Since teacher/professor is the main topic, it comes after の. “I am a college professor,” would be だいがくのせんせいです(daigaku no sensei desu) in Japanese.

In the second example, の is used liked an apostrophe in order to show ownership. Again, since the main idea is  the dog, the word for dog appears after の. You can place any name before の in order to show ownership. For example: しゅうやさんのねこ (Shuuya-san no neko) which means “Shuuya’s cat.”

In the third example, の acts as an apostrophe again. のtells you who the book belongs to. Notice that the のphrase can appear at different places in a sentence. In the example above, the の phrase comes after “This” and before “is.” In this same sentence, これは could be omitted. Then the の phrase would appear first in the sentence. Either sentence is grammatically correct.

You can also have more than one のphrase in a sentence. They can even be right beside each other! See the examples below:

これはわたしのにほんごのほんです。(Kore wa watashi no nihongo no hon desu.)

This is my Japanese book.

わたしのねこのなまえはきりです。(Watashi no neko no namae wa kiri desu.)

My cat’s name is Kiri.

In the first sentence, the の phrase appears twice. The first time it appears it is establishing ownership of the book. The second time it appears it is modifying the book by describing what type of book it is.

In the second sentence, のfirst shows whose cat is being talked about. Then, のprovides further details by telling the name of the cat. ___のなまえmeans “the name of.” It is important to notice that in the second sentence, XはYです form is used. The subject is longer this time (わたしのねこのなまえ), but the structure is still the same. “My cat’s name” is the subject, so it all has to appear before は in this case.

のis a very useful particle and occurs frequently in the Japanese language. When you need to modify a noun with any other noun, you will most likely use の.