関係代名詞（who/which/that/whose）完全ガイド：使い分けと語順をわかりやすく解説！

語順が逆転する理由

日本語は「修飾する節 + 名詞」の順番（私は買った 本）。英語は「名詞 + 関係代名詞 + 節」（the book that I bought）。関係代名詞は「つなぎ目」であり、後ろの節が前の名詞を説明します。この「後ろから説明する」感覚がポイントです。

who / which / that / whose の使い分け

that は who/which の代わりに使えますが、whose の代わりにはなりません。また、コンマ（,）で区切る非制限用法では that は使えず who/which を使います。

主格と目的格の違い

目的格では、文の最後に前置詞が残る形もあります：the person who/that I was talking to（私が話していた相手）。

関係代名詞の省略ルール

ポイント： 後ろの節が主語を必要とするか、目的語を必要とするかを見極めます。目的語が欠けている場合（I bought ___）は省略可能、主語が欠けている場合（___ lives）は省略不可。

日本語との対訳で体感

TOEIC頻出パターン

TOEICでは「空欄の後に何が続くか」で正解を絞ります。名詞が続けば whose、動詞が続けば who/which/that。

よくある質問

練習用の例文 / English Practice Sentences

関係代名詞を実際の文で使いこなしましょう。who は人、which は物、whose は所有、that はどちらにも使えることを確認しながら読んでください。

• The book that I bought yesterday was great. 物には that / which を使う。
• The woman who lives next door is a doctor. 人には who を使う。
• This is the phone which my brother gave me. 物には which を使える。
• The man whose car was stolen called the police. 所有関係は whose を使う。
• I know a place where we can eat lunch. 場所は関係副詞の where。
• The movie that we watched last night was scary. that は物にも使える。
• The student who won the prize studied very hard. 人には who を使う。
• She is the teacher whose class I enjoy most. クラスは先生のものなので whose。
• The house which they bought is near the station. 家は物なので which。
• That is the restaurant that serves great sushi. that は物にも使える。
• The people who live here are very friendly. 複数の人にも who を使う。
• I forgot the password which I set last week. パスワードは物なので which。
• He is the doctor who treated my mother. 医者は人なので who。
• The reason why I left early was the traffic. 理由には why を使う。
• This is the computer that I use every day. that は日常的によく使う。
• The dog which barks a lot belongs to my neighbor. 動物には which を使う。
• I met a friend whose brother works in Tokyo. 兄は友人のものなので whose。
• The city where I was born is famous for temples. 場所には where を使う。
• The email that I sent this morning was ignored. メールは物なので that。
• She told me a story which made me laugh. 話は物なので which。
• The manager who approved the plan is on vacation. 人は who を使う。
• The book that I read was written by a Japanese author. 目的格の that は省略も可能。
• We visited a museum where old paintings are kept. 場所には where を使う。
• The boy whose bike was stolen is my cousin. 自転車は少年のものなので whose。
• That is the song which I liked as a child. 歌は物なので which。
• The team that won the match practiced hard. that はグループにも使える。
• I spoke to a colleague who knows about this issue. 同僚は人なので who。
• The store which opened last month sells coffee. 店は物なので which。
• The letter that arrived today is from my friend. 手紙は物なので that。
• He is someone who always keeps his promises. 人は who を使う。
• The day when we met was rainy and cold. 時には when を使う。
• The restaurant where we ate has great food. 場所には where を使う。
• I bought a gift which my sister will love. 贈り物は物なので which。
• The train that leaves at nine is crowded. that は主格でも使える。
• That is the reason why the project was delayed. 理由には why を使う。
• The article which I wrote was published online. 記事は物なので which。
• We need a plan that everyone can support. that は最も汎用的。
• The teacher who helped me was very kind. 人は who を使う。
• This is the house that my parents built. 家は物なので that。