Modal verbs like can, cannot/can’t, and could are essential for expressing ability—or the lack thereof—across different time frames in English. Below is a comprehensive guide with many examples to help you master their usage.
1. Present Ability with “Can”
Use can to indicate what someone is able to do right now:
- I can swim very well.
- She can speak three languages fluently.
- They can solve complex math problems quickly.
- He can play the guitar beautifully.
- We can cook delicious meals.
- The baby can crawl and stand.
- My dog can fetch the ball every time.
- The computer can process data rapidly.
- I can run a mile in under eight minutes.
- She can dance gracefully.
- They can draw amazing portraits.
- Our team can win the championship.
- The machine can operate continuously for 24 hours.
- He can drive a manual car with ease.
- I can code in several programming languages.
- She can understand difficult concepts quickly.
- They can finish the project on time.
- Our car can reach speeds of up to 150 mph.
- He can lift heavy weights at the gym.
2. Expressing Lack of Ability with “Cannot” / “Can’t”
Use cannot or its contraction can’t to show that someone is not able to do something:
- I cannot swim in the deep ocean.
- She can’t lift that heavy box.
- They cannot solve that puzzle on their own.
- He can’t speak Japanese fluently.
- We cannot attend the meeting today.
- The bird can’t fly after its injury.
- I can’t understand this complex theory.
- She can’t come to the party because she’s busy.
- They can’t find the missing keys.
- He can’t operate the new software.
- I can’t see clearly without my glasses.
- The team can’t win if they don’t practice.
- She can’t remember where she put her phone.
- We can’t travel during the storm.
- He can’t eat spicy food.
- They can’t afford the expensive tickets.
- I can’t hear you over the noise.
- She can’t stay up late on weekdays.
3. Expressing Past Ability with “Could”
Use could to talk about abilities in the past or what someone was able to do before:
- When I was a child, I could climb trees easily.
- She could run very fast when she was young.
- They could solve difficult puzzles in school.
- He could speak French fluently after living in Paris.
- We could see the stars clearly from the countryside.
- I could play the piano when I was in high school.
- She could draw amazing landscapes as a child.
- They could lift heavy weights before their injury.
- He could finish his homework in just one hour.
- We could travel by train across the country.
- I could remember all the details from that day.
- She could sing beautifully in the school choir.
- They could swim across the lake when they were young.
- He could build model airplanes from scratch.
- I could solve the math problem quickly.
- She could dance gracefully at the recital.
- They could speak several languages in high school.
- He could write poems effortlessly.
4. Conditional & Polite Uses of “Could”
Besides expressing past ability, could is also used for polite requests and conditional ability in the present.
- Could you pass the salt, please?
- Could I borrow your car for a day?
- I could help you if you need assistance.
- If I had time, I could join you for dinner.
- Could you please speak slower?
- I could attend the meeting if it is rescheduled.
- Could we try a different approach?
- If you want, you could start the presentation now.
- Could you help me move these boxes?
- I could fix that error with some more time.
Exercises: Expressing ability; Can, cannot, could
1 · Choose Can / Cannot / Could
1. ___ swim?
2. I ___ see without my glasses. It’s difficult for me.
3. When he was five, he ___ read.
4. She ___ drive a car now because she has a driving license.
5. We ___ lift this box; it’s too heavy.
2 · Use Could you / Could I / can’t
1. Teacher, ___ open the window?
2. ___ help me with my homework?
3. Sorry, I ___ come today.
4. ___ borrow your pen?
5. ___ show me the way?
3 · Write Cannot / Could I / Could you
1. I ___ understand this word.
2. ___ speak to the manager? I have a complaint to make.
3. ___ close the door, please?
4. She ___ finish the test on time.
5. ___ have a glass of water?
4 · Choose Can’t / Could not / Could you
1. He ___ solve the puzzle yesterday.
2. I ___ find my keys now.
3. ___ help me lift this?
4. They ___ attend the meeting last week.
5. We ___ hear the teacher clearly. He speaks too fast.
5 · Choose Could not / Can / Could I
1. We ___ play chess after school.
2. ___ borrow your dictionary?
3. He ___ finish his work yesterday.
4. I ___ see the mountains from here.
5. ___ have another cookie?
