During one of my group classes, I overheard a student say the following sentence while talking with her classmate about her love of chocolate:
I can’t stop to eat it!
Later, during the lesson break, I explained to the student that she should have said:
I can’t stop eating it!
Actually, this is quite a common mistake.
The two sentences above are both grammatically correct, but they do not mean the same thing.
“Stop to do something” means that you temporarily stop doing an activity in order to do something else. For example, if you are busy doing some activity such as working, you might say “I can’t stop to eat. This work is too urgent”.
Consider the different meanings of the following examples:
“stop doing it” versus “stop to do it”
“stop sleeping” versus “stop to sleep”
“stop drinking” versus “stop to drink”
“stop working” versus “stop to work“