英語の複文：C1レベル解説
複文の基本
複文とは、主節（Main Clause）と従属節（Subordinate Clause）から構成される文です。C1レベルでは、複雑な従属節の使用と様々な従属節の組み合わせによって、洗練された表現を構築できることが求められます。
1. 高度な関係詞節
短縮関係詞節
関係詞節は、特定の条件下で短縮することができます。
能動態の場合（関係代名詞＋be動詞の省略）：
- The woman [who is] sitting in the corner is my professor.
- Anyone [who is] interested in joining should contact me.
受動態の場合（関係代名詞＋be動詞の省略）：
- The documents [that were] submitted yesterday need your signature.
- The theory [that was] proposed by Einstein revolutionized physics.
複合関係詞の高度な用法
- She gave whatever explanation [that] seemed plausible at the time.
- The government will implement whichever policy [that] yields the best results.
2. 分詞構文の高度な用法
接続詞の代用としての分詞構文
様々な従属接続詞を分詞構文で置き換えることができます：
時（when/while）：
- [While she was] Walking through the park, she bumped into an old friend.
理由（because/as）：
- [Because he was] Having studied abroad, he speaks fluent French.
条件（if）：
- [If it is] Given enough time, the project will succeed.
譲歩（although/though）：
- [Although he was] Having lost everything, he never gave up hope.
完了形・受動態の分詞構文
- Having completed the assignment, she went out with friends.
- Having been criticized by the committee, the proposal was revised.
3. 複雑な動名詞と不定詞のパターン
複雑な動名詞パターン
- The professor insisted on our having completed the research by Friday.
- She objected to his being offered the position without an interview.
- There's no point in their having argued over such a trivial matter.
複雑な不定詞パターン
- She appears to have been working on this project for years.
- The CEO is to be questioned by the committee next week.
- He was foolish to have trusted someone he barely knew.
選択の微妙な違い
- Remember doing something（何かをしたことを覚えている）vs Remember to do something（何かをすることを忘れないようにする）
- Regret doing something（したことを後悔する）vs Regret to inform（残念ながら通知する）
4. 名詞節（that節、wh節）
主語としての名詞節
- That she refused to compromise surprised everyone.
- What they decided in the meeting will affect our entire strategy.
- Whether we'll proceed with the project depends on tomorrow's vote.
目的語としての名詞節
- The board discussed whether to approve the proposal.
- Scientists cannot explain why this phenomenon occurs.
- She questioned how the system would function under pressure.
補語としての名詞節
- The main issue is that resources are limited.
- The advantage became whatever we could make of it.
It + be + 形容詞 + that節の構造
- It is essential that she attend the conference. (仮定法)
- It is surprising that no one noticed the error.
- It is unlikely that prices will decrease in the near future.
5. 適用演習
以下の簡潔な文を、学んだ技術を使って複文に変換してみましょう：
例文：
- 基本：The researcher made a discovery. It revolutionized the field.
- 複文：The researcher, having made a discovery that revolutionized the field, received international recognition.
6. 文体上の注意点
- 複文は形式ばった文章やアカデミックな文脈で特に有効です
- 口語では、より短い複文か単文が好まれることがあります
- 複文の過剰使用は「読みにくい文章」の原因になります
- 効果的な文章は単文、重文、複文のバランスから生まれます
高度な複文の習得は、C1レベルの学習者が「ネイティブライク」な表現力を獲得するための鍵となります。複文を適切に使いこなすことで、論理的関係性をより明確に、より簡潔に、そしてより洗練された方法で表現できるようになります。