I could lead you could lead he could lead we could lead you could lead they could lead
V-ing form
I could be leading you could be leading he could be leading we could be leading you could be leading they could be leading
Perfect
I could have led you could have led he could have led we could have led you could have led they could have led
V-ing perfect
I could have been leading you could have been leading he could have been leading we could have been leading you could have been leading they could have been leading
Negation
Simple form
I couldn't lead you couldn't lead he couldn't lead we couldn't lead you couldn't lead they couldn't lead
V-ing form
I couldn't be leading you couldn't be leading he couldn't be leading we couldn't be leading you couldn't be leading they couldn't be leading
Perfect
I couldn't have led you couldn't have led he couldn't have led we couldn't have led you couldn't have led they couldn't have led
V-ing perfect
I couldn't have been leading you couldn't have been leading he couldn't have been leading we couldn't have been leading you couldn't have been leading they couldn't have been leading
Interrogative form
Simple form
could I lead? could you lead? could he lead? could we lead? could you lead? could they lead?
V-ing form
could I be leading? could you be leading? could he be leading? could we be leading? could you be leading? could they be leading?
Perfect
could I have led? could you have led? could he have led? could we have led? could you have led? could they have led?
V-ing perfect
could I have been leading? could you have been leading? could he have been leading? could we have been leading? could you have been leading? could they have been leading?
Interro-negative form
Simple form
couldn't I lead? couldn't you lead? couldn't he lead? couldn't we lead? couldn't you lead? couldn't they lead?
V-ing form
couldn't I be leading? couldn't you be leading? couldn't he be leading? couldn't we be leading? couldn't you be leading? couldn't they be leading?
Perfect
couldn't I have led? couldn't you have led? couldn't he have led? couldn't we have led? couldn't you have led? couldn't they have led?
V-ing perfect
couldn't I have been leading? couldn't you have been leading? couldn't he have been leading? couldn't we have been leading? couldn't you have been leading? couldn't they have been leading?