基本の説明Overview
関係副詞は、場所・時・理由・方法を表す名詞（先行詞）のあとに置いて、その内容をくわしく説明するはたらきをします。where（場所）、when（時）、why（理由）、how（方法）の4つが代表的です。A relative adverb comes after a noun (the antecedent) that expresses a place, time, reason or method, and adds detail about it. The four main ones are where (place), when (time), why (reason) and how (method).
関係副詞は、〈前置詞＋関係代名詞〉のかわりに使える便利な形です。たとえば the park in which we used to play は the park where we used to play と言いかえられます。in the park という「場所を表す副詞のまとまり」を、where 1語で言いかえていると考えると分かりやすくなります。A relative adverb can replace “preposition + relative pronoun.” For example, the park in which we used to play can become the park where we used to play. Think of where as standing in for the adverb phrase in the park.
| 関係副詞Relative adverb | 先行詞の例Typical antecedents | 言いかえSame meaning with a preposition |
|---|---|---|
| where | the place, the house, the town | in / at / on which |
| when | the day, the year, the time, the season | on / in / at which |
| why | the reason | for which |
| how | (the way) | in which (the way in which) |
関係代名詞と関係副詞を見分けるカギは、関係詞のあとの文です。関係副詞のあとは〈主語＋動詞〉がそろった完全な文になります（This is the park where we used to play.）。一方、関係代名詞のあとは主語や目的語などの名詞が欠けた文になります（This is the park which I like. like の目的語が欠けている）。The key to telling them apart is the clause that follows. After a relative adverb the clause is complete, with both subject and verb (This is the park where we used to play.). After a relative pronoun, a noun such as the subject or object is missing (This is the park which I like. — the object of like is missing).
先行詞が the place, the time, the reason のようにごく一般的な語のときは、先行詞か関係副詞のどちらか一方を省略できます（This is where I live. / That's the reason he left.）。また、where と when はコンマをつけて補足説明にも使えます。When the antecedent is a very general word like the place, the time or the reason, either the antecedent or the relative adverb can be dropped (This is where I live. / That's the reason he left.). Also, where and when can follow a comma to add extra information.
例文で確認Example sentences
① where（場所）1. where (place)
② when（時）2. when (time)
③ why（理由）3. why (reason)
④ how（方法）4. how (method)
⑤ 関係副詞の省略5. Dropping the relative adverb
⑥ 関係代名詞との区別・補足説明6. Pronoun or adverb? / extra information
確認クイズQuick check
空所に適切な語を入れましょう。Fill in each blank with the right word.
- This is the school ___ my father works.
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where — 先行詞は場所（the school）で、あとの文は完全なので where。The antecedent is a place (the school) and the clause is complete, so where. - I remember the day ___ we first met.
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when — 先行詞は時（the day）なので when。The antecedent is a time (the day), so when. - Tell me the reason ___ you were late.
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why — 先行詞は理由（the reason）なので why。The antecedent is a reason (the reason), so why. - This is the town ___ I visited last year. (where / which)
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which — visit は目的語が必要。あとの文は目的語が欠けているので関係代名詞 which。visit needs an object, and the clause lacks it, so the relative pronoun which. - This is ___ she solved the problem.
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how — 「これが彼女がその問題を解決した方法です」。how だけで方法を表せる。“This is the way she solved it.” how alone can express the method. - I like the way ___ he talks. (how / that)
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that（なくてもよい） — the way と how は一緒に使えない。that を使うか、何も入れずに the way he talks とする。the way and how cannot be used together. Use that, or leave it out: the way he talks.
おさえておきたいポイントKey points
- where＝場所、when＝時、why＝理由、how＝方法。先行詞の種類で使い分けるwhere = place, when = time, why = reason, how = method; choose by the kind of antecedent
- 関係副詞のあとは〈主語＋動詞〉がそろった完全な文。関係代名詞のあとは名詞が欠けた文A relative adverb is followed by a complete clause; a relative pronoun is followed by a clause missing a noun
- 関係副詞は〈前置詞＋関係代名詞〉で言いかえられる（the house where = the house in which）A relative adverb can be rewritten as preposition + relative pronoun (the house where = the house in which)
- the place / the time / the reason などは、先行詞か関係副詞のどちらか一方を省略できるWith general antecedents like the place, the time or the reason, either the antecedent or the adverb can be dropped
- how は the way と同時には使わない（the way か how のどちらか一方）Never use how and the way together; choose one
- where と when は、コンマをつけて「そしてそこで／そのとき」と補足説明にも使えるwhere and when can follow a comma to add “and there / and then…”