問 1
Every light in their house is off and their car is gone, so they ( ) already left for the airport.
- should have
- can't have
- must have
- had to
must have + pp (過去の論理的確信)
must have + pp = 「〜したに違いない」。過去の出来事を強い証拠に基づき確信する推量。
「must have」
正解"The lights in their house are all off and their car is gone, so they ~ already left for the airport" は過去の確信推量 = 「must have」。形: must have + pp = 「(証拠から) 〜したに違いない」。現在の確信 must be の過去版。ポイント: 話者が手元の証拠から論理的に過去を断定する。義務の must (〜ねばならない) ではない。準1級頻出: must have pp は C1 鉄板、推論を述べる論説・会話で必出。
「should have」
= 「〜すべきだった(のにしなかった)」 ━ 後悔・非難で確信推量でない ━ 確信は must have、should have は不履行の後悔。
「can't have」
= 「〜したはずがない」 ━ 否定の確信で意味が逆 ━ 肯定の確信は must have、can't have は否定推量。
「had to」
= 実際の過去の義務 ━ 推量でなく事実 ━ 推量は must have pp、had to は現実の義務。
✅ なぜ「must have」が正解? この文では「電気が消え車もない(証拠)→もう出発したに違いない」と過去を確信推量するので 「must have」 が正解。should have は「すべきだった(後悔)」、can't have は否定の確信(〜したはずがない)で逆、had to は実際の過去の義務で推量にならない。
| 形 | マーカー | 例 |
|---|---|---|
| must have + pp | 過去の肯定確信 | She must have left. |
| must be + 補語 | 現在の肯定確信 | She must be tired. |
| must have been V-ing | 過去進行の確信 | He must have been sleeping. |
| 否定推量は can't have | must have の否定は can't have | She can't have known. |
| 文型 | 形 | 例 |
|---|---|---|
| 証拠→過去断定 | S must have pp | The ground is wet; it must have rained. |
| 過去進行の確信 | S must have been V-ing | He must have been working late. |
| 受動の確信 | S must have been pp | The window must have been broken by the storm. |
Every single light in their large house is completely off and the family car is nowhere to be seen, so they must have already left for the distant airport hours ago.
彼らの大きな家のあらゆる電気が完全に消え、家族の車もどこにも見当たらないので、彼らは何時間も前にもう遠くの空港へ出発したに違いない。
The expensive antique vase that always stood on the hallway table is now lying shattered on the floor, so the mischievous cat must have knocked it over during the night.
いつも廊下のテーブルにあった高価な骨董の花瓶が今や床に割れて転がっているので、いたずら好きの猫が夜中にそれを倒したに違いない。
She greeted the visiting professor warmly and confidently in fluent perfect French, so she must have lived in Paris for at least several long years at some earlier point in her life.
彼女は訪問教授を流暢で完璧なフランス語で温かく自信たっぷりに迎えたので、人生のどこかでパリに少なくとも数年は住んでいたに違いない。
There were muddy footprints leading directly from the back door all the way to the locked study, so someone must have broken quietly into the house while we were away.
裏口から鍵のかかった書斎まで泥の足跡がまっすぐ続いていたので、私たちが留守の間に誰かが静かに家に侵入したに違いない。
He looked utterly exhausted and could barely keep his tired eyes open during the long afternoon meeting, so he must have stayed up nearly the entire previous night finishing the report.
彼は長い午後の会議中、疲れ切った目をほとんど開けていられないほど消耗して見えたので、前夜ほぼ徹夜で報告書を仕上げたに違いない。
- must have pp (準1級 鉄板)
★ 証拠に基づく過去の確信「〜したに違いない」 ★ 現在版は must be ━ 推論の must であって義務の must ではない
- 否定は can't have
★ must have の否定推量は can't / couldn't have (mustn't have は推量で原則不可)
- ミス防止
should have は「すべきだった(後悔)」で別物、混同注意