Definition of cannot in English:
- Chemistry is one of those things that just cannot be planned for when casting a film.
- At present, if you draw a company pension you cannot go back to work for that company.
- The workload in Bradford is so great that it cannot take on any new clients at present.
Both the one-word form cannot and the two-word form can not are acceptable, but cannot is more common (in the Oxford English Corpus, three times as common). The two-word form is better only in a construction in which not is part of a set phrase, such as ‘not only ... but (also)’: Paul can not only sing well, but he also paints brilliantly.
Definition of cannot in:
- British & World English dictionary