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