I could irrigate you could irrigate she could irrigate we could irrigate you could irrigate they could irrigate
V-ing form
I could be irrigating you could be irrigating she could be irrigating we could be irrigating you could be irrigating they could be irrigating
Perfect
I could have irrigated you could have irrigated she could have irrigated we could have irrigated you could have irrigated they could have irrigated
V-ing perfect
I could have been irrigating you could have been irrigating she could have been irrigating we could have been irrigating you could have been irrigating they could have been irrigating
Negation
Simple form
I could not irrigate you could not irrigate she could not irrigate we could not irrigate you could not irrigate they could not irrigate
V-ing form
I could not be irrigating you could not be irrigating she could not be irrigating we could not be irrigating you could not be irrigating they could not be irrigating
Perfect
I could not have irrigated you could not have irrigated she could not have irrigated we could not have irrigated you could not have irrigated they could not have irrigated
V-ing perfect
I could not have been irrigating you could not have been irrigating she could not have been irrigating we could not have been irrigating you could not have been irrigating they could not have been irrigating
Interrogative form
Simple form
could I irrigate? could you irrigate? could she irrigate? could we irrigate? could you irrigate? could they irrigate?
V-ing form
could I be irrigating? could you be irrigating? could she be irrigating? could we be irrigating? could you be irrigating? could they be irrigating?
Perfect
could I have irrigated? could you have irrigated? could she have irrigated? could we have irrigated? could you have irrigated? could they have irrigated?
V-ing perfect
could I have been irrigating? could you have been irrigating? could she have been irrigating? could we have been irrigating? could you have been irrigating? could they have been irrigating?
Interro-negative form
Simple form
could I not irrigate? could you not irrigate? could she not irrigate? could we not irrigate? could you not irrigate? could they not irrigate?
V-ing form
could I not be irrigating? could you not be irrigating? could she not be irrigating? could we not be irrigating? could you not be irrigating? could they not be irrigating?
Perfect
could I not have irrigated? could you not have irrigated? could she not have irrigated? could we not have irrigated? could you not have irrigated? could they not have irrigated?
V-ing perfect
could I not have been irrigating? could you not have been irrigating? could she not have been irrigating? could we not have been irrigating? could you not have been irrigating? could they not have been irrigating?