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 can't poison you can't poison he can't poison we can't poison you can't poison they can't poison
V-ing form
I can't be poisoning you can't be poisoning he can't be poisoning we can't be poisoning you can't be poisoning they can't be poisoning
Perfect
I can't have poisoned you can't have poisoned he can't have poisoned we can't have poisoned you can't have poisoned they can't have poisoned
V-ing perfect
I can't have been poisoning you can't have been poisoning he can't have been poisoning we can't have been poisoning you can't have been poisoning they can't 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't I poison? can't you poison? can't he poison? can't we poison? can't you poison? can't they poison?
V-ing form
can't I be poisoning? can't you be poisoning? can't he be poisoning? can't we be poisoning? can't you be poisoning? can't they be poisoning?
Perfect
can't I have poisoned? can't you have poisoned? can't he have poisoned? can't we have poisoned? can't you have poisoned? can't they have poisoned?
V-ing perfect
can't I have been poisoning? can't you have been poisoning? can't he have been poisoning? can't we have been poisoning? can't you have been poisoning? can't they have been poisoning?