PE-42: can, could, be able to: Ability
Your first modal verbs — and the rules that govern all of them. Plus the difference between 'I could swim' and 'I was able to escape'.
PE-42: can, could, be able to: Ability
Welcome to the modal verbs — a small family of helper words that add an attitude to a sentence: ability, permission, obligation, certainty. They are wonderfully easy to use, because they refuse to change their shape. No -s, no -ed, no to. We start with the most useful one of all: can.
In this lesson you will learn
- The four rules that govern every modal verb
- can for ability, permission and requests
- could for past ability and polite questions
- be able to — and when you are forced to use it instead
1. The four rules of all modals
- No -s for he/she/it. She can swim, never
she cans. - No "to" after them. I can swim, never
I can to swim. - Questions by inversion — no do/does: Can you swim?
- Negatives with "not": cannot → can't. No don't.
Afsona can speak three languages, but she can't drive.
Afsona uchta tilda gapira oladi, lekin mashina hayday olmaydi.
2. What can does
1Ability
I can swim 500 metres.
2Permission
You can use my pen.
3Requests
Can you help me, please?
4General possibility
It can get very cold here in January.
3. could — the past and the polite
Could has two quite different jobs. First, it is the past of can for general abilities — things you were able to do over a long period.
When I was five, I could already read. My grandmother couldn't write.
Besh yoshimda men allaqachon oʻqiy olardim. Buvim yoza olmasdi.
Second, it makes a request softer and more polite than can — and here it has no past meaning at all.
Could you open the window, please? — Could I borrow your book?
Derazani ochib yubora olasizmi? — Kitobingizni olib turishim mumkinmi?
4. could or was able to?
Here is the difference that exams love. For a general past ability, use could. But for one particular occasion where somebody actually succeeded, English prefers was/were able to or managed to.
could — general ability
- He could run very fast as a boy.
- She could play the piano at six.
was able to — one success
- The fire started, but everyone was able to escape.
- The exam was hard, but I was able to pass.
5. be able to — filling the gaps
Modals have no infinitive, no -ing form and no future of their own. So when you need can in a place where a modal cannot go, be able to steps in.
Future: I will be able to drive next year. I will can
Perfect: I haven't been able to sleep. I haven't could
After another verb: I want to be able to speak Korean.
Kelasi yil mashina hayday olaman. — Uxlay olmadim. — Koreys tilida gapira olishni xohlayman.
6. Common mistakes
I can to speak English.
I can speak English.
She cans play the guitar.
She can play the guitar.
Do you can help me?
Can you help me?
Next year I will can drive.
Next year I will be able to drive.
The test was difficult, but I could finish it.
… but I was able to finish it. (one occasion, success)
Practice
1 Correct it: My brother can to swims very well.
Show answer
My brother can swim very well.
Two rules broken at once: no to after a modal, and no -s on the main verb.
2 could or was able to: The room was dark, but Jasur ? find the switch.
Show answer
was able to — one particular occasion, and he succeeded. (You could also say managed to.)
3 Put into the future: I can speak a little Korean.
Show answer
I will be able to speak a little Korean.
Two modals cannot stand together, so can becomes be able to.
4 Make the request more polite: Can you pass me the salt?
Show answer
Could you pass me the salt, please?
Here could has nothing to do with the past — it simply sounds gentler.
5 Write two sentences about yourself with can and can't.
Show answer
Model: I can ride a bike and cook plov, but I can't swim yet.
Key words — Kalit soʻzlar
- Modal verbmodal feʼl
- Abilityqobiliyat, imkoniyat
- Permissionruxsat
- Requestiltimos
- Be able to...a olmoq
- To manage touddasidan chiqmoq
- To succeedmuvaffaqiyat qozonmoq
- To escapeqochib qutulmoq
- To borrowolib turmoq
- Politexushmuomala
🎯 Remember this
- Modals take a bare verb: no to, no -s, no -ing.
- Questions by inversion, negatives with not — never do/does.
- can = ability, permission, request · could = past ability or politeness.
- One past success → was able to / managed to, not could.
- Two modals never meet: use will be able to, to be able to.