English verb conjugation
CAN FUNCTION

Regular verb: function - functioned - functioned

Affirmation

Simple form	V-ing form
I can function you can function he can function we can function you can function they can function	I can be functioning you can be functioning he can be functioning we can be functioning you can be functioning they can be functioning
Perfect	V-ing perfect
I can have functioned you can have functioned he can have functioned we can have functioned you can have functioned they can have functioned	I can have been functioning you can have been functioning he can have been functioning we can have been functioning you can have been functioning they can have been functioning

Negation

Simple form	V-ing form
I can't function you can't function he can't function we can't function you can't function they can't function	I can't be functioning you can't be functioning he can't be functioning we can't be functioning you can't be functioning they can't be functioning
Perfect	V-ing perfect
I can't have functioned you can't have functioned he can't have functioned we can't have functioned you can't have functioned they can't have functioned	I can't have been functioning you can't have been functioning he can't have been functioning we can't have been functioning you can't have been functioning they can't have been functioning

Interrogative form

Simple form	V-ing form
can I function? can you function? can he function? can we function? can you function? can they function?	can I be functioning? can you be functioning? can he be functioning? can we be functioning? can you be functioning? can they be functioning?
Perfect	V-ing perfect
can I have functioned? can you have functioned? can he have functioned? can we have functioned? can you have functioned? can they have functioned?	can I have been functioning? can you have been functioning? can he have been functioning? can we have been functioning? can you have been functioning? can they have been functioning?

Interro-negative form

Simple form	V-ing form
can't I function? can't you function? can't he function? can't we function? can't you function? can't they function?	can't I be functioning? can't you be functioning? can't he be functioning? can't we be functioning? can't you be functioning? can't they be functioning?
Perfect	V-ing perfect
can't I have functioned? can't you have functioned? can't he have functioned? can't we have functioned? can't you have functioned? can't they have functioned?	can't I have been functioning? can't you have been functioning? can't he have been functioning? can't we have been functioning? can't you have been functioning? can't they have been functioning?