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