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 couldn't irrigate you couldn't irrigate she couldn't irrigate we couldn't irrigate you couldn't irrigate they couldn't irrigate
V-ing form
I couldn't be irrigating you couldn't be irrigating she couldn't be irrigating we couldn't be irrigating you couldn't be irrigating they couldn't be irrigating
Perfect
I couldn't have irrigated you couldn't have irrigated she couldn't have irrigated we couldn't have irrigated you couldn't have irrigated they couldn't have irrigated
V-ing perfect
I couldn't have been irrigating you couldn't have been irrigating she couldn't have been irrigating we couldn't have been irrigating you couldn't have been irrigating they couldn't 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
couldn't I irrigate? couldn't you irrigate? couldn't she irrigate? couldn't we irrigate? couldn't you irrigate? couldn't they irrigate?
V-ing form
couldn't I be irrigating? couldn't you be irrigating? couldn't she be irrigating? couldn't we be irrigating? couldn't you be irrigating? couldn't they be irrigating?
Perfect
couldn't I have irrigated? couldn't you have irrigated? couldn't she have irrigated? couldn't we have irrigated? couldn't you have irrigated? couldn't they have irrigated?
V-ing perfect
couldn't I have been irrigating? couldn't you have been irrigating? couldn't she have been irrigating? couldn't we have been irrigating? couldn't you have been irrigating? couldn't they have been irrigating?