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