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