I could patrol you could patrol he could patrol we could patrol you could patrol they could patrol
V-ing form
I could be patrolling you could be patrolling he could be patrolling we could be patrolling you could be patrolling they could be patrolling
Perfect
I could have patrolled you could have patrolled he could have patrolled we could have patrolled you could have patrolled they could have patrolled
V-ing perfect
I could have been patrolling you could have been patrolling he could have been patrolling we could have been patrolling you could have been patrolling they could have been patrolling
Negation
Simple form
I could not patrol you could not patrol he could not patrol we could not patrol you could not patrol they could not patrol
V-ing form
I could not be patrolling you could not be patrolling he could not be patrolling we could not be patrolling you could not be patrolling they could not be patrolling
Perfect
I could not have patrolled you could not have patrolled he could not have patrolled we could not have patrolled you could not have patrolled they could not have patrolled
V-ing perfect
I could not have been patrolling you could not have been patrolling he could not have been patrolling we could not have been patrolling you could not have been patrolling they could not have been patrolling
Interrogative form
Simple form
could I patrol? could you patrol? could he patrol? could we patrol? could you patrol? could they patrol?
V-ing form
could I be patrolling? could you be patrolling? could he be patrolling? could we be patrolling? could you be patrolling? could they be patrolling?
Perfect
could I have patrolled? could you have patrolled? could he have patrolled? could we have patrolled? could you have patrolled? could they have patrolled?
V-ing perfect
could I have been patrolling? could you have been patrolling? could he have been patrolling? could we have been patrolling? could you have been patrolling? could they have been patrolling?
Interro-negative form
Simple form
could I not patrol? could you not patrol? could he not patrol? could we not patrol? could you not patrol? could they not patrol?
V-ing form
could I not be patrolling? could you not be patrolling? could he not be patrolling? could we not be patrolling? could you not be patrolling? could they not be patrolling?
Perfect
could I not have patrolled? could you not have patrolled? could he not have patrolled? could we not have patrolled? could you not have patrolled? could they not have patrolled?
V-ing perfect
could I not have been patrolling? could you not have been patrolling? could he not have been patrolling? could we not have been patrolling? could you not have been patrolling? could they not have been patrolling?