I can poison you can poison he can poison we can poison you can poison they can poison
V-ing form
I can be poisoning you can be poisoning he can be poisoning we can be poisoning you can be poisoning they can be poisoning
Perfect
I can have poisoned you can have poisoned he can have poisoned we can have poisoned you can have poisoned they can have poisoned
V-ing perfect
I can have been poisoning you can have been poisoning he can have been poisoning we can have been poisoning you can have been poisoning they can have been poisoning
Negation
Simple form
I cannot poison you cannot poison he cannot poison we cannot poison you cannot poison they cannot poison
V-ing form
I cannot be poisoning you cannot be poisoning he cannot be poisoning we cannot be poisoning you cannot be poisoning they cannot be poisoning
Perfect
I cannot have poisoned you cannot have poisoned he cannot have poisoned we cannot have poisoned you cannot have poisoned they cannot have poisoned
V-ing perfect
I cannot have been poisoning you cannot have been poisoning he cannot have been poisoning we cannot have been poisoning you cannot have been poisoning they cannot have been poisoning
Interrogative form
Simple form
can I poison? can you poison? can he poison? can we poison? can you poison? can they poison?
V-ing form
can I be poisoning? can you be poisoning? can he be poisoning? can we be poisoning? can you be poisoning? can they be poisoning?
Perfect
can I have poisoned? can you have poisoned? can he have poisoned? can we have poisoned? can you have poisoned? can they have poisoned?
V-ing perfect
can I have been poisoning? can you have been poisoning? can he have been poisoning? can we have been poisoning? can you have been poisoning? can they have been poisoning?
Interro-negative form
Simple form
can I not poison? can you not poison? can he not poison? can we not poison? can you not poison? can they not poison?
V-ing form
can I not be poisoning? can you not be poisoning? can he not be poisoning? can we not be poisoning? can you not be poisoning? can they not be poisoning?
Perfect
can I not have poisoned? can you not have poisoned? can he not have poisoned? can we not have poisoned? can you not have poisoned? can they not have poisoned?
V-ing perfect
can I not have been poisoning? can you not have been poisoning? can he not have been poisoning? can we not have been poisoning? can you not have been poisoning? can they not have been poisoning?