Dave's ESL Cafe's Student Discussion Forums

[emilywang]

Dear teachers,

Is there any usage or meaning difference between" cannot" and" can not"?
When should I use "cannot"? When should I use "can not"?

Thanks for your reply.

[lotus]

Hi Emily,

A difficult question at best. You will get different answers for sure. Here's my take.

Cannot means not having the ability. It is the negation of can. Its contraction is can't.

Some folks will say only "cannot" should be used, and that it should not be separated as can not. Others may say that they are interchangeable. I'm of the view that there is a difference between the two - especially in speech and connotation.

Here are two sentences saying basically the same thing, but with a subtle difference.

I tried, but I can't turn the screw with this screwdriver.
Hard as I may, I simply can not turn the screw with this screwdriver.

The first sentence is a simple statement of the person's inability to turn the screw with that screwdriver.

The second sentence stresses more emphatically that the person tried hard, and that he simply CAN NOT turn the screw with that screwdriver.

In speech, we would slow down at that point and say CAN NOT emphatically. In my opinion, the use of "cannot" in this sentence would diminish its strength and lose the connotation of a frustrated unsuccessful effort.

The separation of cannot to can not is actually a useful tool. It acts almost like a punctuation. It allow us to slow it down and give it emphatic meaning in written sentences and in voice.


--lotus

[advoca]

As Lotus said, this is a difficult question (and an interesting one too).

Some dictionaries say that cannot is a short version of cannot.

I think it is safe to say that you can use either and you will be correct in every case. I have not been anle to find any example pf a suggestion where this is not acceptable.

But I too. like Lotus, tend to use can not when I want tp place emphasis.

I tell you Emily, I cannot tell the difference between the two. I just can not

[emilywang]

Thanks for the explicit reply.