Grasping the Subtleties: Can or Could in English Grammar

Ellison Claptonreviewed byNataliia Afonina / more about Editorial Process7 min
Created: Jun 6, 2023Last updated: Jun 6, 2023
Can or Could in English Grammar

Have you ever been caught in a linguistic labyrinth, contemplating whether to use ‘can’ or ‘could’? Picture this: you’re describing your ability to play chess – would you say, “I can play chess,” or is “I could play chess” more appropriate? We’ll arm you with the knowledge to confidently navigate such situations by delving into the distinct roles of ‘can’ vs ‘could.’ So keep reading and drill down on the intricacies of English grammar.

What is the Difference Between Could and Can

Diving into English, we encounter a dynamic duo: ‘can’ and ‘could.’ These two belong to a unique family of words called modal verbs. Serving as invaluable aids, they breathe life into the language by adding dimensions of mood, possibility, ability, and necessity to our statements, questions, and requests.

Unlike standard verbs denoting actions or states, modal verbs like ‘can’ and ‘could’ perform a more nuanced role. They interact with other verbs, influencing their meanings to shape the overall sentiment of a sentence. They allow speakers to portray scenarios ranging from certainty to hypothetical, from present to past, and from the ability to permission.

Although ‘can’ and ‘could’ share common characteristics, their usage unveils a fascinating divergence that enhances the richness of English communication. As we progress through this article, we’ll shed more light on the ‘can’ vs ‘could’ grammar rules, deepening your understanding and refining your English fluency.

Understanding ‘Can’: Expressing Ability and Permission

Let’s start with ‘can.’ This word is among most common English modal verbs and carries a straightforward message – ability or permission. Below, we will examine how ‘can’ is used in a sentence.

  • Ability. ‘Can’ is frequently used to express ability or skill in present circumstances. It helps indicate a person’s skill set or physical or mental capacities.

She can speak five languages fluently, including Mandarin and French.

I can’t play the guitar well yet, but I’m confident I’ll improve with practice.

  • Permission. The word commonly denotes permission granted by an authority.

Can I present a different viewpoint on this issue during our next meeting?

Yes, you can use my office while I’m away.

  • Possibility. ‘Can’ also denotes a theoretical likelihood or potential scenario.

If we don’t leave now, we can miss the last train home.

Given his unpredictable nature, he can surprise us with a sudden change in plans.

  • General Truths. Lastly, this modal word can express general truths or scientific facts.

Snakes can dislocate their jaws to consume prey larger than their heads.

Humans can’t survive without water for more than three days.

Exploring ‘Could’: A Modal Verb with Multiple Meanings

Moving ahead, we dive into the intriguing domain of ‘could.’ This modal verb is a linguistic chameleon, deftly adjusting its meaning to fit different contexts.

  • Past Ability. One common use of ‘could’ is to express abilities or skills that existed in the past but not necessarily in the present.

When I was young, I could run a mile in six minutes.

She could play the piano beautifully before her accident.

  • Polite Requests. ‘Could’ is a useful ally for making polite requests, lending a courteous and respectful tone to our sentences.

Could you please pass the salt?

Could I borrow your notes for the meeting?

  • Suggesting. This modal verb is also effective for offering suggestions or advice in a softer, less direct way.

You could try the new Italian restaurant downtown. Their pasta is to die for.

They could consider merging the two departments for better efficiency.

  • Permission. Similar to ‘can,’ ‘could’ is also used to ask for permission, but it often sounds more polite and formal.

Could we start the meeting a bit earlier tomorrow?

Could I use your laptop for a while?

Through understanding the versatile ‘could,’ we acquire a rich toolkit for expressing past abilities, making polite requests, proposing hypothetical scenarios, offering suggestions, and asking for permission, all of which contribute to nuanced and effective communication in English.

Questioning with Can or Could: Rules and Usage

Stepping into interrogative usage, these modal verbs demonstrate remarkable versatility and adaptability in forming questions. ‘Can’ is frequently used to inquire directly about abilities, possibilities, and permission. For instance, when you ask, “Can you swim?” you seek information about someone’s ability. Likewise, “Can it rain tomorrow?” is an inquiry into the possibility of a future event.

However, when ‘can’ is used to ask for permission, the tone is somewhat direct and perceived as too informal or casual in specific contexts. For example, “Can I use your phone?” is a common way of asking for permission, suitable for friendly or informal situations.

On the other hand, ‘could’ often softens the tone of the question, adding a layer of politeness or indirectness. It’s especially useful when asking for permission or making polite requests. “Could I borrow your book?” is considered a more courteous way to ask for the same permission as with ‘can.’

Understanding these rules for questioning with ‘can’ and ‘could’ not only refines our queries but also allows us to modulate formality and politeness in our interactions, leading to more effective and engaging communication in English.


The Conditional World: Using Can vs Could in Hypothetical Situations

The use of ‘can’ in hypothetical sentences is less common, mainly employed to express potential outcomes if certain conditions are met in the present or future. It adds a sense of possibility to these conditions, making them feel more tangible and imminent. For instance, “If you study hard, you can get an A on your test.” In this scenario, achieving an ‘A’ grade is presented as a possible outcome, assuming the condition of diligent studying is fulfilled.

Contrastingly, ‘could’ is frequently deployed to suggest hypothetical situations. It is useful when we want to speculate about what might happen under different conditions, either in the present, future, or even the past. Its usage often instills a sense of speculation, uncertainty, or distance from reality. For example, “If I won the lottery, I could travel worldwide.” Here, ‘could’ indicates that traveling the globe is a possible outcome of winning the lottery – a hypothetical event.

Navigating the realm of hypotheticals with ‘can’ and ‘could’ enriches our conversations, allowing us to explore a range of potential realities and possibilities. This understanding can enable learners to communicate complex thoughts with greater clarity and precision, enhancing overall fluency in English.

Learn the Difference Between Could and Can with Promova

Grammar is always tricky to navigate, especially for non-native English speakers. The subtle distinctions between words and their usage can make all the difference in communication. That’s why Promova offers a comprehensive language learning experience with personalized classes, interactive exercises, and quizzes catering to various learners’ levels. 

However, Promova isn’t just about mastering grammar rules. We also provide tools and resources to help you expand your vocabulary, improve your speaking skills, and learn other aspects of language.

Our Conversation Club is a dynamic forum where learners can practice communicating with native speakers and fellow English language enthusiasts. Engaging in meaningful conversations will build confidence when discussing various topics, including hobbies and interests.

And don’t forget about our blog! It’s filled with insightful articles that provide tips and tricks on learning new words, improving writing, and avoiding common communication errors. For instance, you can read about the best English grammar books and online resources to aid your learning journey.


The distinction between ‘can you’ and ‘could you’ is not just a grammar rule to memorize but a gateway to a more nuanced understanding of English. Their use expresses abilities, requests, possibilities, and hypothetical situations with varying degrees of certainty and formality. By mastering these modal verbs, we enhance our communication skills, adapt our language to different contexts, and enrich our conversations. To better understand these rules, you can use additional resources, like Grammar Monster or Cambridge apps.


Does ‘can’ and ‘could’ usage change in different English dialects?

Yes, regional variations exist in the use of ‘can’ and ‘could.’ For instance, in some dialects of English, ‘can’ might be used more frequently in polite requests or permissions, whereas in others, ‘could’ might be more common.

How do ‘can’ and ‘could’ function in indirect speech?

Both verbs are employed in indirect speech, though the tense often shifts. An example would be, “She mentioned she could attend the workshop,” where the direct speech was, “I can attend the workshop.

Can ‘could’ be used to soften criticism or negative feedback?

Indeed, ‘could’ is often employed to deliver criticism or feedback less directly, making it sound more like a suggestion than a direct command. For example, “You could try to be more punctual in the future.

Does the meaning of ‘can’ and ‘could’ change in negative sentences?

In negative sentences, ‘can’t’ typically indicates a lack of ability or permission, while ‘couldn’t’ often refers to a lack of ability in the past. However, context is key, and other interpretations might be possible depending on the situation.


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