Module 13.1 – the book I bought yesterday – contact clause

So far we have been dealing with sentences that are very simple, such as

わたしは きのう ほんを かいました。I bought a book yesterday.

その ほんは おもしろかったです。 The book was interesting.

You should be able to combine the two like:

The book I bought yesterday was interesting.
きのう かった ほんは おもしろかったです。

This page is an explanation of how to combine 2 sentences like this.

In order to combine 2 sentences by making one into a contact clause, you need to follow these steps:

  1. Decide which sentence to keep as the main sentence and which to convert into the contact clause.
    In this pair, you won’t know if the book is interesting until you read it, so you need to keep the second sentence “The book was interesting” as the main sentence and the first one “I bought a book yesterday” to convert into a contact clause.
  2. Convert the secondary sentence into the plain form but you need to remember:
    1. [change は to が] If the doer of the action of the verb (= the subject) in the secondary sentence is marked with the topic marker は, this は has to be changed to the subject marker が (or の) as no phrase in the contact clause can be the topic of the sentence any more.
    2. [skip the noun] You need to skip the noun which appears in both sentence together with its particle (in this example, ほんを, the book)
      ⇒ わたしが きのう ほんを かった
  3. Place the contact clause in front of the same noun you have skipped above.
    わたしが きのう かった (その)ほんは おもしろかったです。(The (very) book I bought yesterday was interesting.)
    If the noun in the main clause has この/その/あの in front of it like this example, you can usually skip この/その/あの. If you leave them in the sentence, it adds the meaning of “one and only” to the noun.
    ⇒ わたしが きのう かった ほんは おもしろかったです。(The book I bought yesterday was interesting.)
  4. Tidy up.  You can remove any obvious parts which can be left out. In this case, わたしは is not needed.
    きのう かった ほんは おもしろかったです。

Let’s have a look at how the contact clause ends depending on the words we use:


non-pastほんを よむ ひとthe person/people who reads/read books
pastほんを よんだ ひとthe person/people who read the book
negativeほんを よまない ひとthe person/people who doesn’t/don’t read books
negative pastほんを よまなかった ひとthe person/people who didn’t read the book


non-pastかみが ながい ひとthe person/people who has/have long hair
pastかみが ながかった ひとthe person/people who had long hair
negativeかみが ながくない ひとthe person/people who doesn’t/don’t have long hair
negative pastかみが ながくなかった ひとthe person/people who didn’t have long hair


non-pastすしが すき* ひとthe person/people who likes/like sushi
pastすしが すきだった ひとthe person/people who liked sushi
negativeすしが すきじゃない ひとthe person/people who doesn’t/don’t like sushi
negative pastすしが すきじゃなかった ひとthe person/people who didn’t like sushi
*When the clause is in the non-past, the sentence ending だ changes to な


non-pastこどもが だいがくせいひとthe person/people whose child is a university student
pastこどもが だいがくせいだった ひとthe person/people whose child was a university student
negativeこどもが だいがくせいじゃない ひとthe person/people whose child is not a university student
negative pastこどもが だいがくせいじゃなかった ひとthe person/people whose child was not a university student
*When the clause is in the non-past, the sentence ending だ changes to の

As stated above, when you use a non-past clause which ends in a なadjective + だ, you need to change the ending だ to な. If the contact clause ends in a noun + だ, then the だ needs to be changed to の.

Also, as shown below, the subject marker が within a contact clause is often replaced with の without causing any meaning change. However, some が cannot be replaced with の, so don’t change it unless you are sure.

People who have little rubbish are usually rich.

People who have many friends are usually nice.

More Examples

  1. きょねん かった コートが ちいさく なりました。
  2. としょかんで かりた じしょを なくしました。
  3. それは ずっと ききたかった しつもんです。
  4. あかい シャツを きている おとこのごは わたしの おとうと です。
  5. きのうの よる やった しゅくだいは むずかしかった です。
  6. にほんで かった しょうゆは おいしい です。
  7. ちちが きている せびろは イタリアせい です。
  8. ははが よんだ タクシーで たいしかんに いきました。
  9. あにが かいた ノートが ここに あります。
  10. とうきょうから おくった にもつが きょう とどきました。

Vocab for the above examples

コートnouncoat, court (for tennis, volleyball, etc.)
しつもんnounquestion, inquiry
しょうゆnounsoy sauce
せびろnounbusiness suit, a jacket
ノートnounnotebook, exercise book
Course: JLPT N5