I could staunch you could staunch he could staunch we could staunch you could staunch they could staunch
V-ing form
I could be staunching you could be staunching he could be staunching we could be staunching you could be staunching they could be staunching
Perfect
I could have staunched you could have staunched he could have staunched we could have staunched you could have staunched they could have staunched
V-ing perfect
I could have been staunching you could have been staunching he could have been staunching we could have been staunching you could have been staunching they could have been staunching
Negation
Simple form
I couldn't staunch you couldn't staunch he couldn't staunch we couldn't staunch you couldn't staunch they couldn't staunch
V-ing form
I couldn't be staunching you couldn't be staunching he couldn't be staunching we couldn't be staunching you couldn't be staunching they couldn't be staunching
Perfect
I couldn't have staunched you couldn't have staunched he couldn't have staunched we couldn't have staunched you couldn't have staunched they couldn't have staunched
V-ing perfect
I couldn't have been staunching you couldn't have been staunching he couldn't have been staunching we couldn't have been staunching you couldn't have been staunching they couldn't have been staunching
Interrogative form
Simple form
could I staunch? could you staunch? could he staunch? could we staunch? could you staunch? could they staunch?
V-ing form
could I be staunching? could you be staunching? could he be staunching? could we be staunching? could you be staunching? could they be staunching?
Perfect
could I have staunched? could you have staunched? could he have staunched? could we have staunched? could you have staunched? could they have staunched?
V-ing perfect
could I have been staunching? could you have been staunching? could he have been staunching? could we have been staunching? could you have been staunching? could they have been staunching?
Interro-negative form
Simple form
couldn't I staunch? couldn't you staunch? couldn't he staunch? couldn't we staunch? couldn't you staunch? couldn't they staunch?
V-ing form
couldn't I be staunching? couldn't you be staunching? couldn't he be staunching? couldn't we be staunching? couldn't you be staunching? couldn't they be staunching?
Perfect
couldn't I have staunched? couldn't you have staunched? couldn't he have staunched? couldn't we have staunched? couldn't you have staunched? couldn't they have staunched?
V-ing perfect
couldn't I have been staunching? couldn't you have been staunching? couldn't he have been staunching? couldn't we have been staunching? couldn't you have been staunching? couldn't they have been staunching?