I can shift you can shift he can shift we can shift you can shift they can shift
V-ing form
I can be shifting you can be shifting he can be shifting we can be shifting you can be shifting they can be shifting
Perfect
I can have shifted you can have shifted he can have shifted we can have shifted you can have shifted they can have shifted
V-ing perfect
I can have been shifting you can have been shifting he can have been shifting we can have been shifting you can have been shifting they can have been shifting
Negation
Simple form
I can't shift you can't shift he can't shift we can't shift you can't shift they can't shift
V-ing form
I can't be shifting you can't be shifting he can't be shifting we can't be shifting you can't be shifting they can't be shifting
Perfect
I can't have shifted you can't have shifted he can't have shifted we can't have shifted you can't have shifted they can't have shifted
V-ing perfect
I can't have been shifting you can't have been shifting he can't have been shifting we can't have been shifting you can't have been shifting they can't have been shifting
Interrogative form
Simple form
can I shift? can you shift? can he shift? can we shift? can you shift? can they shift?
V-ing form
can I be shifting? can you be shifting? can he be shifting? can we be shifting? can you be shifting? can they be shifting?
Perfect
can I have shifted? can you have shifted? can he have shifted? can we have shifted? can you have shifted? can they have shifted?
V-ing perfect
can I have been shifting? can you have been shifting? can he have been shifting? can we have been shifting? can you have been shifting? can they have been shifting?
Interro-negative form
Simple form
can't I shift? can't you shift? can't he shift? can't we shift? can't you shift? can't they shift?
V-ing form
can't I be shifting? can't you be shifting? can't he be shifting? can't we be shifting? can't you be shifting? can't they be shifting?
Perfect
can't I have shifted? can't you have shifted? can't he have shifted? can't we have shifted? can't you have shifted? can't they have shifted?
V-ing perfect
can't I have been shifting? can't you have been shifting? can't he have been shifting? can't we have been shifting? can't you have been shifting? can't they have been shifting?