I could roar you could roar he could roar we could roar you could roar they could roar
V-ing form
I could be roaring you could be roaring he could be roaring we could be roaring you could be roaring they could be roaring
Perfect
I could have roared you could have roared he could have roared we could have roared you could have roared they could have roared
V-ing perfect
I could have been roaring you could have been roaring he could have been roaring we could have been roaring you could have been roaring they could have been roaring
Negation
Simple form
I could not roar you could not roar he could not roar we could not roar you could not roar they could not roar
V-ing form
I could not be roaring you could not be roaring he could not be roaring we could not be roaring you could not be roaring they could not be roaring
Perfect
I could not have roared you could not have roared he could not have roared we could not have roared you could not have roared they could not have roared
V-ing perfect
I could not have been roaring you could not have been roaring he could not have been roaring we could not have been roaring you could not have been roaring they could not have been roaring
Interrogative form
Simple form
could I roar? could you roar? could he roar? could we roar? could you roar? could they roar?
V-ing form
could I be roaring? could you be roaring? could he be roaring? could we be roaring? could you be roaring? could they be roaring?
Perfect
could I have roared? could you have roared? could he have roared? could we have roared? could you have roared? could they have roared?
V-ing perfect
could I have been roaring? could you have been roaring? could he have been roaring? could we have been roaring? could you have been roaring? could they have been roaring?
Interro-negative form
Simple form
could I not roar? could you not roar? could he not roar? could we not roar? could you not roar? could they not roar?
V-ing form
could I not be roaring? could you not be roaring? could he not be roaring? could we not be roaring? could you not be roaring? could they not be roaring?
Perfect
could I not have roared? could you not have roared? could he not have roared? could we not have roared? could you not have roared? could they not have roared?
V-ing perfect
could I not have been roaring? could you not have been roaring? could he not have been roaring? could we not have been roaring? could you not have been roaring? could they not have been roaring?