I can pen you can pen he can pen we can pen you can pen they can pen
V-ing form
I can be penning you can be penning he can be penning we can be penning you can be penning they can be penning
Perfect
I can have penned you can have penned he can have penned we can have penned you can have penned they can have penned
V-ing perfect
I can have been penning you can have been penning he can have been penning we can have been penning you can have been penning they can have been penning
Negation
Simple form
I cannot pen you cannot pen he cannot pen we cannot pen you cannot pen they cannot pen
V-ing form
I cannot be penning you cannot be penning he cannot be penning we cannot be penning you cannot be penning they cannot be penning
Perfect
I cannot have penned you cannot have penned he cannot have penned we cannot have penned you cannot have penned they cannot have penned
V-ing perfect
I cannot have been penning you cannot have been penning he cannot have been penning we cannot have been penning you cannot have been penning they cannot have been penning
Interrogative form
Simple form
can I pen? can you pen? can he pen? can we pen? can you pen? can they pen?
V-ing form
can I be penning? can you be penning? can he be penning? can we be penning? can you be penning? can they be penning?
Perfect
can I have penned? can you have penned? can he have penned? can we have penned? can you have penned? can they have penned?
V-ing perfect
can I have been penning? can you have been penning? can he have been penning? can we have been penning? can you have been penning? can they have been penning?
Interro-negative form
Simple form
can I not pen? can you not pen? can he not pen? can we not pen? can you not pen? can they not pen?
V-ing form
can I not be penning? can you not be penning? can he not be penning? can we not be penning? can you not be penning? can they not be penning?
Perfect
can I not have penned? can you not have penned? can he not have penned? can we not have penned? can you not have penned? can they not have penned?
V-ing perfect
can I not have been penning? can you not have been penning? can he not have been penning? can we not have been penning? can you not have been penning? can they not have been penning?