I can fell you can fell she can fell we can fell you can fell they can fell
V-ing form
I can be felling you can be felling she can be felling we can be felling you can be felling they can be felling
Perfect
I can have felled you can have felled she can have felled we can have felled you can have felled they can have felled
V-ing perfect
I can have been felling you can have been felling she can have been felling we can have been felling you can have been felling they can have been felling
Negation
Simple form
I cannot fell you cannot fell she cannot fell we cannot fell you cannot fell they cannot fell
V-ing form
I cannot be felling you cannot be felling she cannot be felling we cannot be felling you cannot be felling they cannot be felling
Perfect
I cannot have felled you cannot have felled she cannot have felled we cannot have felled you cannot have felled they cannot have felled
V-ing perfect
I cannot have been felling you cannot have been felling she cannot have been felling we cannot have been felling you cannot have been felling they cannot have been felling
Interrogative form
Simple form
can I fell? can you fell? can she fell? can we fell? can you fell? can they fell?
V-ing form
can I be felling? can you be felling? can she be felling? can we be felling? can you be felling? can they be felling?
Perfect
can I have felled? can you have felled? can she have felled? can we have felled? can you have felled? can they have felled?
V-ing perfect
can I have been felling? can you have been felling? can she have been felling? can we have been felling? can you have been felling? can they have been felling?
Interro-negative form
Simple form
can I not fell? can you not fell? can she not fell? can we not fell? can you not fell? can they not fell?
V-ing form
can I not be felling? can you not be felling? can she not be felling? can we not be felling? can you not be felling? can they not be felling?
Perfect
can I not have felled? can you not have felled? can she not have felled? can we not have felled? can you not have felled? can they not have felled?
V-ing perfect
can I not have been felling? can you not have been felling? can she not have been felling? can we not have been felling? can you not have been felling? can they not have been felling?