English verb conjugation
CAN ADD

Regular verb: add - added - added

Affirmation

Simple form	V-ing form
I can add you can add she can add we can add you can add they can add	I can be adding you can be adding she can be adding we can be adding you can be adding they can be adding
Perfect	V-ing perfect
I can have added you can have added she can have added we can have added you can have added they can have added	I can have been adding you can have been adding she can have been adding we can have been adding you can have been adding they can have been adding

Negation

Simple form	V-ing form
I cannot add you cannot add she cannot add we cannot add you cannot add they cannot add	I cannot be adding you cannot be adding she cannot be adding we cannot be adding you cannot be adding they cannot be adding
Perfect	V-ing perfect
I cannot have added you cannot have added she cannot have added we cannot have added you cannot have added they cannot have added	I cannot have been adding you cannot have been adding she cannot have been adding we cannot have been adding you cannot have been adding they cannot have been adding

Interrogative form

Simple form	V-ing form
can I add? can you add? can she add? can we add? can you add? can they add?	can I be adding? can you be adding? can she be adding? can we be adding? can you be adding? can they be adding?
Perfect	V-ing perfect
can I have added? can you have added? can she have added? can we have added? can you have added? can they have added?	can I have been adding? can you have been adding? can she have been adding? can we have been adding? can you have been adding? can they have been adding?

Interro-negative form

Simple form	V-ing form
can I not add? can you not add? can she not add? can we not add? can you not add? can they not add?	can I not be adding? can you not be adding? can she not be adding? can we not be adding? can you not be adding? can they not be adding?
Perfect	V-ing perfect
can I not have added? can you not have added? can she not have added? can we not have added? can you not have added? can they not have added?	can I not have been adding? can you not have been adding? can she not have been adding? can we not have been adding? can you not have been adding? can they not have been adding?