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