I can stroke you can stroke he can stroke we can stroke you can stroke they can stroke
V-ing form
I can be stroking you can be stroking he can be stroking we can be stroking you can be stroking they can be stroking
Perfect
I can have stroked you can have stroked he can have stroked we can have stroked you can have stroked they can have stroked
V-ing perfect
I can have been stroking you can have been stroking he can have been stroking we can have been stroking you can have been stroking they can have been stroking
Negation
Simple form
I cannot stroke you cannot stroke he cannot stroke we cannot stroke you cannot stroke they cannot stroke
V-ing form
I cannot be stroking you cannot be stroking he cannot be stroking we cannot be stroking you cannot be stroking they cannot be stroking
Perfect
I cannot have stroked you cannot have stroked he cannot have stroked we cannot have stroked you cannot have stroked they cannot have stroked
V-ing perfect
I cannot have been stroking you cannot have been stroking he cannot have been stroking we cannot have been stroking you cannot have been stroking they cannot have been stroking
Interrogative form
Simple form
can I stroke? can you stroke? can he stroke? can we stroke? can you stroke? can they stroke?
V-ing form
can I be stroking? can you be stroking? can he be stroking? can we be stroking? can you be stroking? can they be stroking?
Perfect
can I have stroked? can you have stroked? can he have stroked? can we have stroked? can you have stroked? can they have stroked?
V-ing perfect
can I have been stroking? can you have been stroking? can he have been stroking? can we have been stroking? can you have been stroking? can they have been stroking?
Interro-negative form
Simple form
can I not stroke? can you not stroke? can he not stroke? can we not stroke? can you not stroke? can they not stroke?
V-ing form
can I not be stroking? can you not be stroking? can he not be stroking? can we not be stroking? can you not be stroking? can they not be stroking?
Perfect
can I not have stroked? can you not have stroked? can he not have stroked? can we not have stroked? can you not have stroked? can they not have stroked?
V-ing perfect
can I not have been stroking? can you not have been stroking? can he not have been stroking? can we not have been stroking? can you not have been stroking? can they not have been stroking?