I can screen you can screen he can screen we can screen you can screen they can screen
V-ing form
I can be screening you can be screening he can be screening we can be screening you can be screening they can be screening
Perfect
I can have screened you can have screened he can have screened we can have screened you can have screened they can have screened
V-ing perfect
I can have been screening you can have been screening he can have been screening we can have been screening you can have been screening they can have been screening
Negation
Simple form
I cannot screen you cannot screen he cannot screen we cannot screen you cannot screen they cannot screen
V-ing form
I cannot be screening you cannot be screening he cannot be screening we cannot be screening you cannot be screening they cannot be screening
Perfect
I cannot have screened you cannot have screened he cannot have screened we cannot have screened you cannot have screened they cannot have screened
V-ing perfect
I cannot have been screening you cannot have been screening he cannot have been screening we cannot have been screening you cannot have been screening they cannot have been screening
Interrogative form
Simple form
can I screen? can you screen? can he screen? can we screen? can you screen? can they screen?
V-ing form
can I be screening? can you be screening? can he be screening? can we be screening? can you be screening? can they be screening?
Perfect
can I have screened? can you have screened? can he have screened? can we have screened? can you have screened? can they have screened?
V-ing perfect
can I have been screening? can you have been screening? can he have been screening? can we have been screening? can you have been screening? can they have been screening?
Interro-negative form
Simple form
can I not screen? can you not screen? can he not screen? can we not screen? can you not screen? can they not screen?
V-ing form
can I not be screening? can you not be screening? can he not be screening? can we not be screening? can you not be screening? can they not be screening?
Perfect
can I not have screened? can you not have screened? can he not have screened? can we not have screened? can you not have screened? can they not have screened?
V-ing perfect
can I not have been screening? can you not have been screening? can he not have been screening? can we not have been screening? can you not have been screening? can they not have been screening?