I could waste you could waste she could waste we could waste you could waste they could waste
V-ing form
I could be wasting you could be wasting she could be wasting we could be wasting you could be wasting they could be wasting
Perfect
I could have wasted you could have wasted she could have wasted we could have wasted you could have wasted they could have wasted
V-ing perfect
I could have been wasting you could have been wasting she could have been wasting we could have been wasting you could have been wasting they could have been wasting
Negation
Simple form
I could not waste you could not waste she could not waste we could not waste you could not waste they could not waste
V-ing form
I could not be wasting you could not be wasting she could not be wasting we could not be wasting you could not be wasting they could not be wasting
Perfect
I could not have wasted you could not have wasted she could not have wasted we could not have wasted you could not have wasted they could not have wasted
V-ing perfect
I could not have been wasting you could not have been wasting she could not have been wasting we could not have been wasting you could not have been wasting they could not have been wasting
Interrogative form
Simple form
could I waste? could you waste? could she waste? could we waste? could you waste? could they waste?
V-ing form
could I be wasting? could you be wasting? could she be wasting? could we be wasting? could you be wasting? could they be wasting?
Perfect
could I have wasted? could you have wasted? could she have wasted? could we have wasted? could you have wasted? could they have wasted?
V-ing perfect
could I have been wasting? could you have been wasting? could she have been wasting? could we have been wasting? could you have been wasting? could they have been wasting?
Interro-negative form
Simple form
could I not waste? could you not waste? could she not waste? could we not waste? could you not waste? could they not waste?
V-ing form
could I not be wasting? could you not be wasting? could she not be wasting? could we not be wasting? could you not be wasting? could they not be wasting?
Perfect
could I not have wasted? could you not have wasted? could she not have wasted? could we not have wasted? could you not have wasted? could they not have wasted?
V-ing perfect
could I not have been wasting? could you not have been wasting? could she not have been wasting? could we not have been wasting? could you not have been wasting? could they not have been wasting?