English verb conjugation
CAN COMBINE

Regular verb: combine - combined - combined

Affirmation

Simple form	V-ing form
I can combine you can combine he can combine we can combine you can combine they can combine	I can be combining you can be combining he can be combining we can be combining you can be combining they can be combining
Perfect	V-ing perfect
I can have combined you can have combined he can have combined we can have combined you can have combined they can have combined	I can have been combining you can have been combining he can have been combining we can have been combining you can have been combining they can have been combining

Negation

Simple form	V-ing form
I cannot combine you cannot combine he cannot combine we cannot combine you cannot combine they cannot combine	I cannot be combining you cannot be combining he cannot be combining we cannot be combining you cannot be combining they cannot be combining
Perfect	V-ing perfect
I cannot have combined you cannot have combined he cannot have combined we cannot have combined you cannot have combined they cannot have combined	I cannot have been combining you cannot have been combining he cannot have been combining we cannot have been combining you cannot have been combining they cannot have been combining

Interrogative form

Simple form	V-ing form
can I combine? can you combine? can he combine? can we combine? can you combine? can they combine?	can I be combining? can you be combining? can he be combining? can we be combining? can you be combining? can they be combining?
Perfect	V-ing perfect
can I have combined? can you have combined? can he have combined? can we have combined? can you have combined? can they have combined?	can I have been combining? can you have been combining? can he have been combining? can we have been combining? can you have been combining? can they have been combining?

Interro-negative form

Simple form	V-ing form
can I not combine? can you not combine? can he not combine? can we not combine? can you not combine? can they not combine?	can I not be combining? can you not be combining? can he not be combining? can we not be combining? can you not be combining? can they not be combining?
Perfect	V-ing perfect
can I not have combined? can you not have combined? can he not have combined? can we not have combined? can you not have combined? can they not have combined?	can I not have been combining? can you not have been combining? can he not have been combining? can we not have been combining? can you not have been combining? can they not have been combining?