Warning, this verb may not exist. Conjugation is given as example.
Affirmation
Simple form
I can lengthen lengthen you can lengthen lengthen he can lengthen lengthen we can lengthen lengthen you can lengthen lengthen they can lengthen lengthen
V-ing form
I can be lengthen lengthening you can be lengthen lengthening he can be lengthen lengthening we can be lengthen lengthening you can be lengthen lengthening they can be lengthen lengthening
Perfect
I can have lengthen lengthened you can have lengthen lengthened he can have lengthen lengthened we can have lengthen lengthened you can have lengthen lengthened they can have lengthen lengthened
V-ing perfect
I can have been lengthen lengthening you can have been lengthen lengthening he can have been lengthen lengthening we can have been lengthen lengthening you can have been lengthen lengthening they can have been lengthen lengthening
Negation
Simple form
I cannot lengthen lengthen you cannot lengthen lengthen he cannot lengthen lengthen we cannot lengthen lengthen you cannot lengthen lengthen they cannot lengthen lengthen
V-ing form
I cannot be lengthen lengthening you cannot be lengthen lengthening he cannot be lengthen lengthening we cannot be lengthen lengthening you cannot be lengthen lengthening they cannot be lengthen lengthening
Perfect
I cannot have lengthen lengthened you cannot have lengthen lengthened he cannot have lengthen lengthened we cannot have lengthen lengthened you cannot have lengthen lengthened they cannot have lengthen lengthened
V-ing perfect
I cannot have been lengthen lengthening you cannot have been lengthen lengthening he cannot have been lengthen lengthening we cannot have been lengthen lengthening you cannot have been lengthen lengthening they cannot have been lengthen lengthening
Interrogative form
Simple form
can I lengthen lengthen? can you lengthen lengthen? can he lengthen lengthen? can we lengthen lengthen? can you lengthen lengthen? can they lengthen lengthen?
V-ing form
can I be lengthen lengthening? can you be lengthen lengthening? can he be lengthen lengthening? can we be lengthen lengthening? can you be lengthen lengthening? can they be lengthen lengthening?
Perfect
can I have lengthen lengthened? can you have lengthen lengthened? can he have lengthen lengthened? can we have lengthen lengthened? can you have lengthen lengthened? can they have lengthen lengthened?
V-ing perfect
can I have been lengthen lengthening? can you have been lengthen lengthening? can he have been lengthen lengthening? can we have been lengthen lengthening? can you have been lengthen lengthening? can they have been lengthen lengthening?
Interro-negative form
Simple form
can I not lengthen lengthen? can you not lengthen lengthen? can he not lengthen lengthen? can we not lengthen lengthen? can you not lengthen lengthen? can they not lengthen lengthen?
V-ing form
can I not be lengthen lengthening? can you not be lengthen lengthening? can he not be lengthen lengthening? can we not be lengthen lengthening? can you not be lengthen lengthening? can they not be lengthen lengthening?
Perfect
can I not have lengthen lengthened? can you not have lengthen lengthened? can he not have lengthen lengthened? can we not have lengthen lengthened? can you not have lengthen lengthened? can they not have lengthen lengthened?
V-ing perfect
can I not have been lengthen lengthening? can you not have been lengthen lengthening? can he not have been lengthen lengthening? can we not have been lengthen lengthening? can you not have been lengthen lengthening? can they not have been lengthen lengthening?