I can leave you can leave she can leave we can leave you can leave they can leave
V-ing form
I can be leaving you can be leaving she can be leaving we can be leaving you can be leaving they can be leaving
Perfect
I can have left you can have left she can have left we can have left you can have left they can have left
V-ing perfect
I can have been leaving you can have been leaving she can have been leaving we can have been leaving you can have been leaving they can have been leaving
Negation
Simple form
I can't leave you can't leave she can't leave we can't leave you can't leave they can't leave
V-ing form
I can't be leaving you can't be leaving she can't be leaving we can't be leaving you can't be leaving they can't be leaving
Perfect
I can't have left you can't have left she can't have left we can't have left you can't have left they can't have left
V-ing perfect
I can't have been leaving you can't have been leaving she can't have been leaving we can't have been leaving you can't have been leaving they can't have been leaving
Interrogative form
Simple form
can I leave? can you leave? can she leave? can we leave? can you leave? can they leave?
V-ing form
can I be leaving? can you be leaving? can she be leaving? can we be leaving? can you be leaving? can they be leaving?
Perfect
can I have left? can you have left? can she have left? can we have left? can you have left? can they have left?
V-ing perfect
can I have been leaving? can you have been leaving? can she have been leaving? can we have been leaving? can you have been leaving? can they have been leaving?
Interro-negative form
Simple form
can't I leave? can't you leave? can't she leave? can't we leave? can't you leave? can't they leave?
V-ing form
can't I be leaving? can't you be leaving? can't she be leaving? can't we be leaving? can't you be leaving? can't they be leaving?
Perfect
can't I have left? can't you have left? can't she have left? can't we have left? can't you have left? can't they have left?
V-ing perfect
can't I have been leaving? can't you have been leaving? can't she have been leaving? can't we have been leaving? can't you have been leaving? can't they have been leaving?