How do you use "can't have vs mustn't have" in a sentence?

He can't have stolen it - he was with me all day. They can't have arrived yet - the plane just landed. She can't have known about the surprise. You can't have read the whole book already!

can't have vs mustn't have

Q: What does "can't have vs mustn't have" mean?

Deductions about impossible past events 'Can't have + past participle' expresses certainty something didn't happen: 'She can't have left - her car is here.' Stronger than 'mustn't have' which is rare and formal in British English.

Grammar Pattern BritishAmericanAustralian ★★★★☆ Common Neutral

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Meaning: Deductions about impossible past events

对不可能发生的过去事件进行推断

Deducciones sobre eventos pasados imposibles

起こり得なかった過去の出来事についての推論

일어날 수 없었던 과거 사건에 대한 추론

'Can't have + past participle' expresses certainty something didn't happen: 'She can't have left - her car is here.' Stronger than 'mustn't have' which is rare and formal in British English.

'Can't have + 过去分词'表示确定某事没有发生：'She can't have left - her car is here.' 比'mustn't have'更强烈，后者在英式英语中少见且正式。

'Can't have + participio' expresa certeza de que algo no ocurrió: 'She can't have left - her car is here.' Más fuerte que 'mustn't have' que es raro y formal en inglés británico.

「Can't have + 過去分詞」は何かが起こらなかったという確信を表します：「She can't have left - her car is here.」「mustn't have」より強く、後者はイギリス英語では稀でフォーマルです。

'Can't have + 과거분사'는 어떤 일이 일어나지 않았다는 확신을 표현한다: 'She can't have left - her car is here.' 'mustn't have'보다 강하며, mustn't have는 영국 영어에서 드물고 격식적이다.

Examples

He can't have stolen it - he was with me all day.
他不可能偷的——他整天都和我在一起。
Él no puede haberlo robado - estuvo conmigo todo el día.
彼が盗んだはずがない——一日中私と一緒だった。
그가 훔쳤을 리가 없다 — 하루 종일 나와 함께 있었으니까.
They can't have arrived yet - the plane just landed.
他们不可能已经到了——飞机刚降落。
No pueden haber llegado todavía - el avión acaba de aterrizar.
彼らがもう着いたはずがない——飛行機が着陸したばかりです。
그들이 벌써 도착했을 리가 없다 — 비행기가 방금 착륙했는데.
She can't have known about the surprise.
她不可能知道那个惊喜。
Ella no puede haber sabido sobre la sorpresa.
彼女がサプライズを知っていたはずがない。
그녀가 서프라이즈를 알았을 리가 없다.
You can't have read the whole book already!
你不可能已经读完整本书了！
¡No puedes haber leído todo el libro ya!
もう本を全部読んだはずがないでしょう！
벌써 책을 다 읽었을 리가 없잖아!

Pronunciation

Usage Guide

Context: spoken, written, everyday

Tone: deductive

✓ Do Say

She can't have forgotten - I reminded her twice.
她不可能忘了——我提醒过她两次。
Ella no puede haberse olvidado - la recordé dos veces.
彼女が忘れたはずがない——2回も思い出させた。
그녀가 잊었을 리 없어 — 두 번이나 상기시켰거든.
The restaurant can't have closed - it's only 8pm.
餐厅不可能关门了——才晚上8点。
El restaurante no puede haber cerrado - son solo las 8pm.
レストランが閉まっていたはずがない——まだ8時だ。
식당이 문을 닫았을 리 없어 — 아직 저녁 8시밖에 안 됐는데.
He can't have understood the instructions.
他不可能理解那些说明。
Él no puede haber entendido las instrucciones.
彼が説明を理解したはずがない。
그가 설명을 이해했을 리 없다.
They can't have received my message yet.
他们不可能已经收到我的消息。
No pueden haber recibido mi mensaje todavía.
彼らはまだ私のメッセージを受け取っていないはずだ。
그들이 아직 내 메시지를 받았을 리 없다.
She can't have forgotten.
她不可能忘了。
No puede haberse olvidado.
彼女が忘れたはずがありません。
그녀가 잊었을 리 없다.

✗ Don't Say

She can't forgot. (need 'have forgotten')
She can't forgot.（需要'have forgotten'）
She can't forgot. (se necesita 'have forgotten')
She can't forgot.（「have forgotten」が必要）
She can't forgot.（'have forgotten'이 필요）
She mustn't have forgot. (rare; prefer 'can't have')
She mustn't have forgot.（少见；优先使用'can't have'）
She mustn't have forgot. (poco frecuente; es preferible 'can't have')
She mustn't have forgot.（稀；「can't have」を優先）
She mustn't have forgot.（드문 표현; 'can't have'를 사용）

Origin & History

Negative deduction modal

Cultural Context

Era: Modern

Generation: All ages

Social background: Universal