Cannot or Can Not: How to Use Can Not vs. Cannot Correctly

When you say that you are unable to do something, do you say that you cannot or can not do that? Both these spellings are acceptable and can be found in formal writing, and yet their meaning is slightly different. Read on to figure out what’s this difference and to never confuse these two phrases again.

Cannot or Can Not: Understanding the Basics

Cannot or Can Not


Meaning of Can Not

We find that “can not” is usually found when it’s part of some other construction, like “not only… but also.” For example, “We can not only swim but also play tennis.” In this context, it emphasizes that there are two different abilities, swimming and playing tennis. The use of “can not” is quite rare and it’s important to notice that it slightly changes the meaning of the sentence.

Meaning of Cannot

“Cannot” is a single word formed by combining “can” and “not.” Generally, it is used to express the impossibility or incapability of doing something. It negates the ability or permission to perform an action. For example, “We cannot lift that heavy box” or “You cannot enter without a ticket.”

Practical Guidance

When to Use Can Not

When we want to emphasize the negative aspect of a sentence, we can use “can not.” For example, “I can not stress enough how important it is to proofread your work.” In this case, we want to emphasize that it is impossible to stress enough the importance of proofreading.

Another situation where we can use “can not” is when we want to use it as part of a construction such as “not only…but also.” For example, “Not only can we not afford the rent, but also the utilities are too high.” Here, we use “can not” to emphasize the negative aspect of the situation.

When to Use Cannot

In most cases, we should use “cannot” instead of “can not.” “Cannot” is more common and recommended, especially in formal writing. For example, “We cannot accept late submissions for this assignment.” In this case, we are stating a rule or policy, and using “cannot” makes it clear and direct.

Another situation where we should use “cannot” is when we want to express the idea of impossibility. For example, “I cannot believe how fast time flies.” In this case, we are expressing our amazement at how quickly time passes, and using “cannot” emphasizes the idea of impossibility.

Related Confused Words

When it comes to the usage of “cannot” and “can not,” there are other related words that can cause confusion. In this section, we’ll discuss some of these words and how they differ from “cannot” and “can not.”

Cannot vs. can’t

“Cannot” and “can’t” are often used interchangeably, but there is a subtle difference between the two. “Cannot” is the proper spelling of the word, while “can’t” is a contraction of “cannot.” In other words, “can’t” is simply a shorter version of “cannot.”

Both “cannot” and “can’t” mean the same thing: that something is impossible or not allowed. For example, “I cannot lift this heavy box” and “I can’t lift this heavy box” have the same meaning. However, “cannot” is more formal and is generally used in written English, while “can’t” is more informal and is often used in spoken English.

Can not vs. could not

“Can not” and “could not” are two different verb phrases that are often confused with each other. “Can not” is the negative form of “can,” while “could not” is the negative form of “could.”

“Can not” is used to express the inability to do something in the present or future, while “could not” is used to express the inability to do something in the past. For example, “I can not swim” means that I am currently unable to swim, while “I could not swim” means that I was unable to swim in the past.

It’s important to note that “can not” is not the same as “cannot.” “Cannot” is a single word that is used to express the same thing as “can not.”

Comparative Analysis

Differences in Meaning

When deciding between “cannot” and “can not,” it’s important to understand the differences in their meanings. “Cannot” is a contraction of “can not,” and they are often used interchangeably. However, “cannot” is more commonly used in formal writing, while “can not” is more common in informal writing.

For example, in a sentence like “We cannot afford to lose this opportunity,” “cannot” is the more appropriate choice. On the other hand, in a sentence like “We can not wait to see you,” “can not” is more appropriate.

While both phrases have the same basic meaning, using “cannot” can add a sense of formality and seriousness to your writing. However, using “can not” can help to convey a more casual, conversational tone.

Contextual Appropriateness

The decision to use “cannot” or “can not” also depends on the context in which it is being used. In general, “cannot” is used when referring to an inability to do something, while “can not” is used when referring to the ability to do something.

For example, in a sentence like “I cannot speak French,” “cannot” is the appropriate choice because it refers to an inability to speak the language. On the other hand, in a sentence like “I can not believe how beautiful this view is,” “can not” is appropriate because it refers to the ability to believe something.

Cannot vs. Can Not Examples

Examples of “Cannot” 

  • You cannot make a crab walk straight.
  • Time past cannot be called back again.
  • She cannot afford a new dress.
  • The athletes cannot compete in any athletic events while suspended.
  • I cannot only grow begonias, but also identify them.

Examples of “Can Not” 

  • Roads can not only ruin the countryside, but also divide communities.
  • This product can not only smooth throat, but also cure the common faucitis and stomatocace effectively.
  • The CIP system can not only clean the medicines, but also control the microorganism’s cleaning.
  • It can not only cure the disease, but also postpone caducity and strengthen the body.
  • Prompt action by local people can not only prevent ultimate demolition, but also save many thousands of pounds in repair costs.

Quiz: “Cannot” vs. “Can Not”

Let’s test your knowledge on the usage of “cannot” and “can not”. Below are some sentences, and you need to decide whether “cannot” or “can not” is the correct word to use.

  1. I _____ wait to see the new movie.
  2. She _____ believe what she just heard.
  3. We _____ afford to buy a new car.
  4. They _____ decide which restaurant to go to.
  5. You _____ always get what you want.


  1. cannot
  2. can not
  3. cannot
  4. can not
  5. can not

Frequently Asked Questions

We understand that there may be some confusion when it comes to using “cannot” and “can not” interchangeably. Here are some frequently asked questions that we hope will clear things up:

Is “can not” one word or two?

“Can not” can be written as two separate words, but it is also acceptable to write it as one word, “cannot.” However, it is important to note that “can’t” is a contraction of “cannot,” and it is not always suitable for formal writing.

When should I use “cannot” versus “can not”?

Generally, “cannot” is preferred in more formal or professional situations such as work-related stuff, presentations, and ad copy. It is also the preferred form in British English. On the other hand, if you’re doing some informal writing or trying to emphasize a negative idea, using “can not” is acceptable for everyday writing.

Can I use “can not” in place of “cannot” in any situation?

While “can not” can be used in place of “cannot” in some situations, it is important to note that “cannot” is the more widely accepted form. Additionally, using “can not” in formal writing may be frowned upon, so it is best to use “cannot” in such situations.

Is there a difference in meaning between “cannot” and “can not”?

No, there is no difference in meaning between “cannot” and “can not.” Both forms express the same idea of inability or prohibition.

We hope these frequently asked questions have helped to clear up any confusion you may have had about using “cannot” and “can not.” Remember, when in doubt, it’s always best to use “cannot” in formal writing and “can not” in informal writing.