英検準1級のsufficient・adequate・substantial・considerable・excessiveの違い｜独自40問・全解説

英検準1級のsufficient・adequate・substantial・considerable・excessiveは、量・質・程度を評価する際の類義語ですが、重要な違いがあります。sufficientは目的に対して十分、adequateは基準を満たして適切、substantialは規模や量が大きい、considerableは程度がかなり大きい、excessiveは必要以上で過剰、という基本です。大きい金額が必ず十分とは限らず、基準を満たしただけの設備が非常に優れているとも限りません。

慶英会の独自40問（4択16・和文英訳8・誤文訂正8・長文2題8問）を全解答と和訳付きで無料公開します。日本英語検定協会による準1級の試験内容にある語句空所補充・長文内容一致・英文要約・意見英作文に役立つ語法を題材にしています。公式過去問ではありません。

結論｜「十分」「適切」「大きい」「かなり」「過剰」の違い

substantialとconsiderable、sufficientとadequateには重なる意味があります。設問では、必要な閾値か規模の大きさか、過剰であることが問題なのかを目的語・基準・結果で判断してください。

演習A｜語彙4択16問

A1. The council could not proceed because it lacked ___ evidence to justify the proposed construction plan.

1. excessive
2. sufficient
3. considerable
4. temporary

A2. Inspectors confirmed that the emergency exits provided ___ access for wheelchair users under the specified standards.

1. considerable
2. excessive
3. adequate
4. substantial

A3. The foundation made a ___ investment in new school libraries, funding the renovation of twelve buildings.

1. sufficient
2. excessive
3. adequate
4. substantial

A4. The research announcement attracted ___ interest from teachers across several regions.

1. considerable
2. excessive
3. sufficient
4. inadequate

A5. The park introduced limits on ___ noise from outdoor events late at night.

1. adequate
2. sufficient
3. excessive
4. considerable

A6. The experiment cannot begin until the team has collected ___ samples to test its main hypothesis.

1. substantial
2. excessive
3. considerable
4. sufficient

A7. The shelter provided ___ heating and lighting that met the authority’s minimum safety requirements.

1. adequate
2. excessive
3. considerable
4. substantial

A8. The town received a ___ grant large enough to build an entirely new public swimming pool.

1. excessive
2. substantial
3. temporary
4. inadequate

A9. The new bus route generated ___ discussion among residents, even before the trial started.

1. excessive
2. sufficient
3. considerable
4. adequate

A10. Doctors warned that ___ use of the equipment could put unnecessary pressure on the system.

1. excessive
2. adequate
3. sufficient
4. considerable

A11. The teacher said that five minutes was not ___ time to read and understand the passage.

1. considerable
2. excessive
3. sufficient
4. substantial

A12. The committee judged the emergency shelter’s food supply ___ for the three-day stay under the stated criteria.

1. excessive
2. substantial
3. considerable
4. adequate

A13. The company announced a ___ reduction in its operating costs after reorganizing logistics.

1. sufficient
2. substantial
3. adequate
4. excessive

A14. The city’s plan faced ___ public opposition, with residents organizing meetings in six districts.

1. considerable
2. adequate
3. sufficient
4. excessive

A15. The laboratory limited ___ exposure to bright light because it could damage sensitive specimens.

1. substantial
2. sufficient
3. excessive
4. adequate

A16. The manager confirmed that the reserve fund was ___ to cover the known repair costs, with no additional borrowing needed.

1. considerable
2. excessive
3. substantial
4. sufficient

演習B｜和文英訳8問

「十分な」だけに頼らず、具体的な目的・必要量・評価の基準を英文に入れてください。

B1. 「決定を下すには十分な証拠が必要だ。」

B2. 「設備は最低限の安全基準を満たしている。」

B3. 「市は教育に多額の投資を行った。」

B4. 「その提案は住民からかなりの関心を集めた。」

B5. 「過度な使用は機械の故障につながる可能性がある。」

B6. 「その学校には全員が勉強できる十分な机がある。」

B7. 「避難所には指定された人数に適切な暖房がある。」

B8. 「予算が大きいことと事業に十分であることは同じではない。」

演習C｜言い換えと誤文訂正8問

必要量・規模・適切性を取り違えた英文を意味に合わせて修正します。

C1. The committee had excessive evidence to justify the proposal, meaning it finally had exactly what was needed.

C2. The building had considerable emergency exits under the specified safety code.

C3. The charity invested an adequate amount that was unusually large by any historical measure.

C4. The plan received sufficient public attention, meaning people across many regions discussed it intensely.

C5. The teacher warned students not to make adequate use of the equipment because doing so could cause damage.

C6. The reserve fund was substantial to pay the full repair bill, so no further funding was needed.

C7. The school provided substantial ventilation that met the minimum requirement, although it was not exceptional.

C8. The data showed that the company had made an adequate 40 percent reduction in operating expenses, far beyond its original target.

演習D｜予算・公共交通の独自長文2題8問

必要な額と大きな額、基準を満たす状態と過剰な状態を区別しましょう。

独自長文1｜図書館の予算と利用状況

A city planned to renovate several libraries. The mayor announced a substantial investment, but an independent committee warned that a large budget was not necessarily sufficient to complete every renovation. Engineers estimated that two buildings would require additional repairs, so officials set aside extra funds before making final commitments. Inspectors later confirmed that the temporary reading rooms had adequate lighting and ventilation under the city’s stated standards. The renovation proposal attracted considerable interest from local families, who attended public meetings in several neighborhoods. However, some residents complained about excessive noise during evening construction. The city responded by limiting work hours and publishing a revised schedule. In its report, the committee distinguished the size of the investment, the adequacy of facilities, the sufficiency of funds, the level of public interest and noise that exceeded acceptable limits.

D1. Did a substantial budget automatically mean every renovation could be funded?

D2. What did inspectors judge adequate?

D3. What indicated considerable public interest?

D4. What problem did residents describe as excessive?

独自長文2｜地域のバスサービスと利用者調査

A rural district wanted to introduce an evening bus service. The proposal generated considerable discussion because many residents depended on private cars. The council secured a substantial grant to buy vehicles, but it was uncertain whether the grant would be sufficient to cover operating costs over several years. Transport officials inspected the proposed stops and confirmed that most offered adequate space for passengers using wheelchairs. Residents also raised concerns about excessive traffic around the school entrance at dismissal time. To respond, planners proposed moving one stop and limiting the number of buses using a narrow road. A trial would measure ridership before the council decided whether to continue the service. Officials emphasized that interest, funding size, practical adequacy and long-term affordability had to be evaluated separately.

D5. What generated considerable discussion?

D6. Why was the substantial grant not automatically sufficient?

D7. What feature of most bus stops was judged adequate?

D8. What excessive condition near the school concerned residents?

全解答・全和訳と根拠

A｜4択16問

A1：B sufficient。判断を正当化するのに必要な証拠の量が足りない＝sufficient evidence。 和訳：議会は建設案を正当化する十分な証拠がなかったため先に進めなかった。

A2：C adequate。定められた基準を満たす適切な利用条件＝adequate access。 和訳：検査官は非常口が指定基準に照らして車椅子利用者に適切なアクセスを提供すると確認した。

A3：D substantial。12棟の改装を支える規模の大きな投資＝substantial investment。 和訳：財団は新しい学校図書館に大規模な投資を行い、12棟の改装費を賄った。

A4：A considerable。多くの教員のかなり強い関心＝considerable interest。 和訳：研究発表は複数地域の教員からかなりの関心を集めた。

A5：C excessive。夜間の度を越した騒音＝excessive noise。 和訳：公園は深夜の屋外イベントによる過度な騒音を制限した。

A6：D sufficient。検証に必要な数を満たす＝sufficient samples。 和訳：研究班が主要仮説を検証するのに十分な試料を集めるまで実験を始められない。

A7：A adequate。最低安全要件を満たした設備＝adequate heating and lighting。 和訳：避難施設は当局の最低安全要件を満たす暖房と照明を備えていた。

A8：B substantial。新しいプール全体を建設できるほど大きい助成金＝substantial grant。 和訳：町は新たな公共プールを建設できるほど大きな助成金を受け取った。

A9：C considerable。試行前から多くの議論が起きた＝considerable discussion。 和訳：新しいバス路線は試験運行前から住民の間でかなりの議論を引き起こした。

A10：A excessive。必要な範囲を超えた使いすぎ＝excessive use。 和訳：担当医は機器の過度な使用がシステムに不必要な負担をかけ得ると警告した。

A11：C sufficient。読解に必要な時間が足りない＝not sufficient time。 和訳：教員は5分では長文を読んで理解するのに十分な時間ではないと述べた。

A12：D adequate。3日滞在という指定条件を満たす備蓄量＝adequate。 和訳：委員会は明示された基準に照らし3日間の滞在に必要な食料が十分に備蓄されていると判断した。

A13：B substantial。物流改革後に大幅な費用削減があった＝substantial reduction。 和訳：企業は物流の再編後、運営費を大幅に削減したと発表した。

A14：A considerable。6地区で会議が開かれるほどかなりの反対がある＝considerable opposition。 和訳：その市の計画はかなりの住民反対に直面し、6地区で集会が開かれた。

A15：C excessive。過度な光照射＝excessive exposure。 和訳：研究室は敏感な試料を損傷し得る過度な強い光への曝露を制限した。

A16：D sufficient。既知の修理費用を全額賄えるかという閾値を満たすsufficient to cover。 和訳：責任者は準備金が既知の修理費を賄うのに十分で、追加借入が不要だと確認した。

B｜英作文8問

B1：Sufficient evidence is needed before a decision can be made. 解説：必要量・閾値を満たすsufficient evidence。

B2：The facilities are adequate under the minimum safety standards. 解説：必要な質・機能を満たすadequate。

B3：The city made a substantial investment in education. 解説：規模が大きいsubstantial investment。

B4：The proposal attracted considerable interest from residents. 解説：considerable interestは程度の大きさ。

B5：Excessive use may lead to equipment failure. 解説：excessive use＝必要以上の使いすぎ。

B6：The school has sufficient desks for all students to study. 解説：必要な数を満たすsufficient desks。

B7：The shelter has adequate heating for the specified number of people. 解説：基準を満たす質・機能adequate heating。

B8：A substantial budget is not necessarily sufficient for the project. 解説：substantialは規模、sufficientは目的に対する充足。

C｜訂正8問

C1：The committee had sufficient evidence to justify the proposal. 理由：必要な根拠が揃ったことをexcessiveと言わずsufficientで表す。

C2：The building had adequate emergency exits under the specified safety code. 理由：基準を満たす適切性＝adequate。

C3：The charity invested a substantial amount that was unusually large by any historical measure. 理由：金額の大きさに焦点があるならsubstantial。

C4：The plan received considerable public attention, with intense discussion across many regions. 理由：関心の規模の大きさはconsiderable。

C5：The teacher warned students not to make excessive use of the equipment because doing so could cause damage. 理由：過剰使用を警告するのでexcessive。

C6：The reserve fund was sufficient to pay the full repair bill, so no further funding was needed. 理由：目的を達成できるだけの金額＝sufficient to do。

C7：The school provided adequate ventilation that met the minimum requirement, although it was not exceptional. 理由：最低基準を満たす＝adequate。substantialは量の大きさ。

C8：The data showed that the company had made a substantial 40 percent reduction in operating expenses, far beyond its original target. 理由：大幅な削減を意味するsubstantial reduction。

D｜長文8問

D1：No. The committee said it might not be sufficient for all work. 本文根拠：金額の大きさと目的の充足は別。

D2：Lighting and ventilation in the temporary reading rooms. 本文根拠：明示された施設基準を満たした。

D3：Families attended meetings in several neighborhoods. 本文根拠：住民の関心の大きさを示す。

D4：Noise during evening construction. 本文根拠：限度を超える夜間騒音。

D5：The proposed evening bus service. 本文根拠：多くの議論が起きた対象。

D6：It might not cover operating costs over several years. 本文根拠：車両購入費の大きな助成と継続運営費は別。

D7：Space for passengers using wheelchairs. 本文根拠：利用者の条件に合う場所の広さ。

D8：Traffic around the school entrance at dismissal time. 本文根拠：混雑・交通量の度を超えた状態。

英文要約の重要ポイント｜substantialでもsufficientとは限らない

原文：The city received a substantial grant, but it was uncertain whether the money would be sufficient to maintain the service.。大きな助成金を受け取ったことと、長期運営に十分なことは別です。The grant fully covered future operating costs.と要約すると、原文にない確定情報を加えてしまいます。Despite receiving a large grant, the city remained uncertain about long-term funding.が安全な言い換えです。

意見英作文への応用

Governments should provide sufficient funding for public facilities and maintain adequate safety standards. However, excessive spending without clear evidence of benefits should be avoided.（政府は公共施設に十分な資金を配分し、適切な安全水準を維持すべきだ。しかし利益の明確な根拠がない過剰支出は避けるべきだ。）必要量と過剰を区別することで説得力が増します。

7日間で復習する順序

1. 1日目：5語を「目的への十分さ」「規模」「超過」に分類。
2. 2日目：A1〜A8で必要条件の有無を確認。
3. 3日目：A9〜A16で規模と過剰の差を確認。
4. 4日目：B8問を自力で英訳。
5. 5日目：C8問を訂正して誤答の理由を説明。
6. 6日目：D2長文で何が十分で何が未確定かを整理。
7. 7日目：準1級の公式長文・英文要約へ転用。

FAQ

sufficientとadequateは同じ意味ですか？

どちらも必要な水準を満たす意味があります。sufficientは目的を達成するだけの量・程度、adequateは基準に照らして適切な質・量というニュアンスがあります。

substantialとconsiderableの違いは？

意味は近いですが、substantialは大きな規模や実質的な量、considerableは関心・努力・時間などを含め「かなりの程度」を示すときによく使われます。必ず置き換え可能とは限らないため連語を確認します。

excessiveは必ず悪い意味ですか？

必要・適切な程度を超えているという否定的な評価が含まれるのが一般的です。excessive noise、excessive spendingなどで使われます。

関連無料教材と慶英会の学習相談

不足・欠如の語法40問／評価・測定・推定の語法40問／資金・補助・寄付の語法40問／準1級無料教材一覧。

慶英会では、英検準1級の類義語を本文の事実・条件に沿って読み、英文要約や意見英作文までつなげる個別指導を行っています。最大1か月完全無料体験・学習相談はこちら。

参考にした公式情報

日本英語検定協会｜準1級試験内容／同｜準1級公式過去問。全40問と英文は慶英会による独自教材です。