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