I could snowplow you could snowplow she could snowplow we could snowplow you could snowplow they could snowplow
V-ing form
I could be snowplowing you could be snowplowing she could be snowplowing we could be snowplowing you could be snowplowing they could be snowplowing
Perfect
I could have snowplowed you could have snowplowed she could have snowplowed we could have snowplowed you could have snowplowed they could have snowplowed
V-ing perfect
I could have been snowplowing you could have been snowplowing she could have been snowplowing we could have been snowplowing you could have been snowplowing they could have been snowplowing
Negation
Simple form
I could not snowplow you could not snowplow she could not snowplow we could not snowplow you could not snowplow they could not snowplow
V-ing form
I could not be snowplowing you could not be snowplowing she could not be snowplowing we could not be snowplowing you could not be snowplowing they could not be snowplowing
Perfect
I could not have snowplowed you could not have snowplowed she could not have snowplowed we could not have snowplowed you could not have snowplowed they could not have snowplowed
V-ing perfect
I could not have been snowplowing you could not have been snowplowing she could not have been snowplowing we could not have been snowplowing you could not have been snowplowing they could not have been snowplowing
Interrogative form
Simple form
could I snowplow? could you snowplow? could she snowplow? could we snowplow? could you snowplow? could they snowplow?
V-ing form
could I be snowplowing? could you be snowplowing? could she be snowplowing? could we be snowplowing? could you be snowplowing? could they be snowplowing?
Perfect
could I have snowplowed? could you have snowplowed? could she have snowplowed? could we have snowplowed? could you have snowplowed? could they have snowplowed?
V-ing perfect
could I have been snowplowing? could you have been snowplowing? could she have been snowplowing? could we have been snowplowing? could you have been snowplowing? could they have been snowplowing?
Interro-negative form
Simple form
could I not snowplow? could you not snowplow? could she not snowplow? could we not snowplow? could you not snowplow? could they not snowplow?
V-ing form
could I not be snowplowing? could you not be snowplowing? could she not be snowplowing? could we not be snowplowing? could you not be snowplowing? could they not be snowplowing?
Perfect
could I not have snowplowed? could you not have snowplowed? could she not have snowplowed? could we not have snowplowed? could you not have snowplowed? could they not have snowplowed?
V-ing perfect
could I not have been snowplowing? could you not have been snowplowing? could she not have been snowplowing? could we not have been snowplowing? could you not have been snowplowing? could they not have been snowplowing?