I can sink you can sink he can sink we can sink you can sink they can sink
V-ing form
I can be sinking you can be sinking he can be sinking we can be sinking you can be sinking they can be sinking
Perfect
I can have sunk you can have sunk he can have sunk we can have sunk you can have sunk they can have sunk
V-ing perfect
I can have been sinking you can have been sinking he can have been sinking we can have been sinking you can have been sinking they can have been sinking
Negation
Simple form
I cannot sink you cannot sink he cannot sink we cannot sink you cannot sink they cannot sink
V-ing form
I cannot be sinking you cannot be sinking he cannot be sinking we cannot be sinking you cannot be sinking they cannot be sinking
Perfect
I cannot have sunk you cannot have sunk he cannot have sunk we cannot have sunk you cannot have sunk they cannot have sunk
V-ing perfect
I cannot have been sinking you cannot have been sinking he cannot have been sinking we cannot have been sinking you cannot have been sinking they cannot have been sinking
Interrogative form
Simple form
can I sink? can you sink? can he sink? can we sink? can you sink? can they sink?
V-ing form
can I be sinking? can you be sinking? can he be sinking? can we be sinking? can you be sinking? can they be sinking?
Perfect
can I have sunk? can you have sunk? can he have sunk? can we have sunk? can you have sunk? can they have sunk?
V-ing perfect
can I have been sinking? can you have been sinking? can he have been sinking? can we have been sinking? can you have been sinking? can they have been sinking?
Interro-negative form
Simple form
can I not sink? can you not sink? can he not sink? can we not sink? can you not sink? can they not sink?
V-ing form
can I not be sinking? can you not be sinking? can he not be sinking? can we not be sinking? can you not be sinking? can they not be sinking?
Perfect
can I not have sunk? can you not have sunk? can he not have sunk? can we not have sunk? can you not have sunk? can they not have sunk?
V-ing perfect
can I not have been sinking? can you not have been sinking? can he not have been sinking? can we not have been sinking? can you not have been sinking? can they not have been sinking?