Deduction present and past: must be / can't be, must have done

🎯 Po co Ci to? Zakres rozszerzony. Wnioskowanie to modal + odpowiedni bezokolicznik: must be (na pewno jest), must have been (na pewno był), can't have done (na pewno nie zrobił), might have been doing (może akurat robił). Do tego modale oceny przeszłości: should have (trzeba było), needn't have (niepotrzebnie), could have (mogłeś, a nie zrobiłeś). To najczęściej sprawdzany punkt transformacji na poziomie rozszerzonym.

W kursie: 9.4 [R] (What's wrong? — deduction), 8.5 [R].

📐 Gramatyka w pigułce — budowa

Odniesienie	Forma	Przykład
teraz, stan	modal + be / bezokolicznik	It must be cold outside.
teraz, w trakcie	modal + be + -ing	She must be sleeping — the lights are off.
przeszłość	modal + have + III forma	He must have done it — there was nobody else there.
przeszłość, w trakcie	modal + have been + -ing	At 5 p.m. John might have been taking a driving test.

📐 Gramatyka w pigułce — skala pewności o przeszłości

Stopień	Twierdzenie	Przeczenie
prawie pewne	must have done	can't / couldn't have done
możliwe	may / might / could have done	may not / might not have done

Uwaga na asymetrię: przeciwieństwem must have jest can't have, nie mustn't have.

📐 Gramatyka w pigułce — ocena przeszłości

Konstrukcja	Znaczenie	Przykład
should / ought to have done	trzeba było, a nie zrobiłeś (wyrzut, żal)	You ought to have washed the glasses before serving the drinks.
shouldn't have done	nie trzeba było, a zrobiłeś	I shouldn't have said that.
needn't have done	zrobiłeś, ale niepotrzebnie	You needn't have come — I'm going to deal with it myself.
didn't need to do	nie było potrzeby (i zwykle nie zrobiłeś)	I didn't need to cook — they'd brought dinner.
could have done	mogłeś, a nie zrobiłeś (możliwość / lekki wyrzut)	You could have taken a taxi from the airport.
may not have done	być może nie zrobiłeś	You may not have heard about this place, but it's amazing.

⚠️ Typowe błędy

• ✗ He mustn't have seen us. → ✓ He can't have seen us.
• ✗ You should had told me. → ✓ You should have told me.
• ✗ She must be tired yesterday. → ✓ She must have been tired yesterday.
• ✗ You needn't have come użyte, gdy ktoś nie przyszedł → ✓ You didn't need to come. (needn't have = przyszedł niepotrzebnie)
• ✗ He must have been do it. → ✓ He must have done it.

💭 Pomyśl

💭 Pomyśl: „You needn't have bought bread" i „You didn't need to buy bread". Po którym zdaniu w kuchni leżą dwa bochenki?

Sprawdź odpowiedź

Po pierwszym. You needn't have bought bread mówi, że chleb został kupiony, choć nie było potrzeby (był już w domu, stąd dwa bochenki). You didn't need to buy bread stwierdza tylko, że potrzeby nie było, i zwykle znaczy, że chleb nie został kupiony. Modal z have zawsze mówi o tym, co realnie się stało.

✍️ Ćwiczenia

1. The ground is wet. It ___ (rain) during the night.
2. She didn't answer the phone. She ___ (sleep) — it was 2 a.m.
3. He got 100% in the test. He ___ (study) really hard.
4. You ___ (not/leave) the door open! Now the cat's gone.
5. That ___ (not/be) Marek you saw — he was with me all evening.
6. Thanks for the flowers, but you ___ (not/buy) them — it's not my birthday.

Sprawdź odpowiedź

1. must have rained · 2. must have been sleeping · 3. must have studied · 4. shouldn't have left · 5. can't have been · 6. needn't have bought.

📋 Na egzaminie

1. Transformacja: I'm sure Tom didn't take your keys — he wasn't here. HAVE → Tom ___ your keys — he wasn't here.
2. Transformacja: It was a mistake to lend him the car. SHOULD → I ___ him the car.
3. Transformacja: It wasn't necessary for you to wait, but you did. NEEDN'T → You ___ .
4. Tłumaczenie fragmentu: Whoever you saw, ___ (to nie mógł być John) — he's in Canada.

Sprawdź odpowiedź

1. Tom can't have taken your keys… · 2. I shouldn't have lent him the car. · 3. You needn't have waited. · 4. …it can't have been John — he's in Canada.