English verb conjugation
CAN ERR

Regular verb: err - erred - erred

Affirmation

Simple form	V-ing form
I can err you can err she can err we can err you can err they can err	I can be erring you can be erring she can be erring we can be erring you can be erring they can be erring
Perfect	V-ing perfect
I can have erred you can have erred she can have erred we can have erred you can have erred they can have erred	I can have been erring you can have been erring she can have been erring we can have been erring you can have been erring they can have been erring

Negation

Simple form	V-ing form
I can't err you can't err she can't err we can't err you can't err they can't err	I can't be erring you can't be erring she can't be erring we can't be erring you can't be erring they can't be erring
Perfect	V-ing perfect
I can't have erred you can't have erred she can't have erred we can't have erred you can't have erred they can't have erred	I can't have been erring you can't have been erring she can't have been erring we can't have been erring you can't have been erring they can't have been erring

Interrogative form

Simple form	V-ing form
can I err? can you err? can she err? can we err? can you err? can they err?	can I be erring? can you be erring? can she be erring? can we be erring? can you be erring? can they be erring?
Perfect	V-ing perfect
can I have erred? can you have erred? can she have erred? can we have erred? can you have erred? can they have erred?	can I have been erring? can you have been erring? can she have been erring? can we have been erring? can you have been erring? can they have been erring?

Interro-negative form

Simple form	V-ing form
can't I err? can't you err? can't she err? can't we err? can't you err? can't they err?	can't I be erring? can't you be erring? can't she be erring? can't we be erring? can't you be erring? can't they be erring?
Perfect	V-ing perfect
can't I have erred? can't you have erred? can't she have erred? can't we have erred? can't you have erred? can't they have erred?	can't I have been erring? can't you have been erring? can't she have been erring? can't we have been erring? can't you have been erring? can't they have been erring?