Modal Verbs of Ability

A2 · ElementaryModal Verbs

Can, could, and be able to let you say what someone is capable of doing, whether that's now, in the past, or in the future.

What you'll learn

  • Can + base verb for present ability (I can swim)
  • Could + base verb for general past ability (I could swim as a child)
  • Be able to fills the gaps can can't reach — future, perfect, infinitive forms
  • Was/were able to (not could) for a single completed past achievement

What someone is capable of doing

Can, could, and be able to all express ability — the capacity to do something, whether physical, mental, or learned.

"She can speak three languages."
"When I was young, I could run fast."

Can vs. be able to

Can is the most common way to express present ability. Be able to means the same thing but can be used in tenses can doesn't have, like the future or the perfect.

"After the course, you will be able to cook Italian food."
"I haven't been able to sleep well this week."

Could vs. was/were able to

Could describes a general ability someone had over a period of time in the past. For one specific, completed achievement, English prefers was/were able to — could can sound odd or even imply it didn't happen.

"Despite the storm, they were able to reach the summit. (one specific achievement)"
"My grandmother could speak five languages. (a general past ability)"

Real English

"She could play the piano at the age of five."
"We won't be able to attend the meeting."
"Were you able to fix the car?"
"After years of practice, she was able to run a marathon."

Watch out

✗We won't can attend the meeting.
✓We won't be able to attend the meeting.

Two modal-like forms can't stack — use be able to after will, not can.

✗Do you can drive?
✓Can you drive?

Don't add do to a question with can — invert can and the subject instead.

✗Despite the storm, they could reach the summit.
✓Despite the storm, they were able to reach the summit.

For one specific, completed past achievement, use was/were able to, not could.

Real life — Talking about skills

"Can you drive?"

"Yes, I can — I've been driving for ten years."

"Could you drive when you were a teenager?"

"No, I couldn't — I learned much later."

Practice

Exercise 1 · Choose the correct sentence

Choose the correct sentence — present ability.

Exercise 2 · Choose the correct sentence

Choose the correct sentence — past ability.

Exercise 3 · Choose the correct negative

Choose the correct negative.

Exercise 4 · Choose the correct question

Choose the correct question.

Exercise 5 · Choose the correct sentence

Choose the correct sentence — future ability.

Exercise 6 · Choose the correct answer

Which phrase must you use where 'can' has no form available, such as after 'will'?

Exercise 7 · Choose the correct sentence

Choose the correct sentence for a specific past achievement (one completed event).

Exercise 8 · Choose the correct sentence

Choose the correct sentence.

Exercise 9 · Complete the sentence

Complete: 'My grandmother ___ (can/speak) five languages when she was younger.'

Exercise 10 · Complete the sentence

Complete: 'I ___ (not/can/come) to the party tomorrow — I'm working.'

Exercise 11 · Sort into groups

can cook
could cook
will be able to cook
was able to cook
can't cook
couldn't cook

0 / 6 sorted

Quick challenge

Five quick questions to check what stuck.

Question 1 / 5

Score: 0/0

Choose the correct sentence.

You learned

  • Can expresses present ability; could expresses general past ability.
  • Be able to fills in tenses can and could don't have, like the future and perfect.
  • For one specific past achievement, use was/were able to instead of could.
  • Can't and couldn't are the simple negatives.

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