Explanation
Use a non-defining relative clause to add extra information about a person, place, or thing. The extra information is not needed to identify the noun.
For example, in "My sister, who lives in Osaka, is coming tomorrow," "My sister" is the main noun, "who lives in Osaka" gives extra information, and the commas show a short pause. The sentence still makes sense without the clause: "My sister is coming tomorrow." Use "who" for people, "which" for things, "where" for places, and "whose" for possession. Japanese often puts this kind of information before the noun, but English puts it after the noun with commas.
非制限用法の関係節は、人・場所・物について追加情報を足すときに使います。その情報がなくても、名詞はすでに分かっています。
例えば "My sister, who lives in Osaka, is coming tomorrow." では、"My sister" が中心の名詞で、"who lives in Osaka" が追加情報です。前後のカンマは、そこで少し区切ることを表します。この関係節を外しても "My sister is coming tomorrow." と意味は通じます。日本語では「大阪に住んでいる妹が明日来ます」のように名詞の前で説明しますが、英語では名詞のあとに続けます。
Examples
- My sister, who lives in Osaka, is coming tomorrow. 大阪に住んでいる妹が、明日来ます。
- Tokyo Tower, which I visited last year, looks beautiful at night. 私が去年訪れた東京タワーは、夜とてもきれいです。
- We went to a small cafe, where we had lunch. 私たちは小さなカフェに行って、そこで昼ごはんを食べました。
- Ms. Brown, whose dog is very noisy, lives next door. 犬がとてもうるさいブラウンさんは、隣に住んでいます。
- Have you met Ken, who sits next to you in class? 授業であなたの隣に座っているケンに会いましたか？
- My old laptop, which I bought in 2018, does not work anymore. 私の古いノートパソコンは、2018年に買ったものですが、もう動きません。
Common Mistakes
Japanese learners often forget the commas or use a defining relative clause by mistake.
Wrong: "My sister who lives in Osaka is coming tomorrow."
Right: "My sister, who lives in Osaka, is coming tomorrow."
They may also use "that" here.
Wrong: "My sister, that lives in Osaka, is coming tomorrow."
Right: "My sister, who lives in Osaka, is coming tomorrow."
日本語の語順のまま、カンマを入れずに書いてしまうミスが多いです。
誤: "My sister who lives in Osaka is coming tomorrow."
正: "My sister, who lives in Osaka, is coming tomorrow."
また、非制限用法では "that" を使ってしまうこともあります。
誤: "My sister, that lives in Osaka, is coming tomorrow."
正: "My sister, who lives in Osaka, is coming tomorrow."