I can begin you can begin he can begin we can begin you can begin they can begin
V-ing form
I can be beginning you can be beginning he can be beginning we can be beginning you can be beginning they can be beginning
Perfect
I can have begun you can have begun he can have begun we can have begun you can have begun they can have begun
V-ing perfect
I can have been beginning you can have been beginning he can have been beginning we can have been beginning you can have been beginning they can have been beginning
Negation
Simple form
I can't begin you can't begin he can't begin we can't begin you can't begin they can't begin
V-ing form
I can't be beginning you can't be beginning he can't be beginning we can't be beginning you can't be beginning they can't be beginning
Perfect
I can't have begun you can't have begun he can't have begun we can't have begun you can't have begun they can't have begun
V-ing perfect
I can't have been beginning you can't have been beginning he can't have been beginning we can't have been beginning you can't have been beginning they can't have been beginning
Interrogative form
Simple form
can I begin? can you begin? can he begin? can we begin? can you begin? can they begin?
V-ing form
can I be beginning? can you be beginning? can he be beginning? can we be beginning? can you be beginning? can they be beginning?
Perfect
can I have begun? can you have begun? can he have begun? can we have begun? can you have begun? can they have begun?
V-ing perfect
can I have been beginning? can you have been beginning? can he have been beginning? can we have been beginning? can you have been beginning? can they have been beginning?
Interro-negative form
Simple form
can't I begin? can't you begin? can't he begin? can't we begin? can't you begin? can't they begin?
V-ing form
can't I be beginning? can't you be beginning? can't he be beginning? can't we be beginning? can't you be beginning? can't they be beginning?
Perfect
can't I have begun? can't you have begun? can't he have begun? can't we have begun? can't you have begun? can't they have begun?
V-ing perfect
can't I have been beginning? can't you have been beginning? can't he have been beginning? can't we have been beginning? can't you have been beginning? can't they have been beginning?