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