I could toll you could toll he could toll we could toll you could toll they could toll
V-ing form
I could be tolling you could be tolling he could be tolling we could be tolling you could be tolling they could be tolling
Perfect
I could have tolled you could have tolled he could have tolled we could have tolled you could have tolled they could have tolled
V-ing perfect
I could have been tolling you could have been tolling he could have been tolling we could have been tolling you could have been tolling they could have been tolling
Negation
Simple form
I could not toll you could not toll he could not toll we could not toll you could not toll they could not toll
V-ing form
I could not be tolling you could not be tolling he could not be tolling we could not be tolling you could not be tolling they could not be tolling
Perfect
I could not have tolled you could not have tolled he could not have tolled we could not have tolled you could not have tolled they could not have tolled
V-ing perfect
I could not have been tolling you could not have been tolling he could not have been tolling we could not have been tolling you could not have been tolling they could not have been tolling
Interrogative form
Simple form
could I toll? could you toll? could he toll? could we toll? could you toll? could they toll?
V-ing form
could I be tolling? could you be tolling? could he be tolling? could we be tolling? could you be tolling? could they be tolling?
Perfect
could I have tolled? could you have tolled? could he have tolled? could we have tolled? could you have tolled? could they have tolled?
V-ing perfect
could I have been tolling? could you have been tolling? could he have been tolling? could we have been tolling? could you have been tolling? could they have been tolling?
Interro-negative form
Simple form
could I not toll? could you not toll? could he not toll? could we not toll? could you not toll? could they not toll?
V-ing form
could I not be tolling? could you not be tolling? could he not be tolling? could we not be tolling? could you not be tolling? could they not be tolling?
Perfect
could I not have tolled? could you not have tolled? could he not have tolled? could we not have tolled? could you not have tolled? could they not have tolled?
V-ing perfect
could I not have been tolling? could you not have been tolling? could he not have been tolling? could we not have been tolling? could you not have been tolling? could they not have been tolling?