I can work you can work he can work we can work you can work they can work
V-ing form
I can be working you can be working he can be working we can be working you can be working they can be working
Perfect
I can have worked you can have worked he can have worked we can have worked you can have worked they can have worked
V-ing perfect
I can have been working you can have been working he can have been working we can have been working you can have been working they can have been working
Negation
Simple form
I cannot work you cannot work he cannot work we cannot work you cannot work they cannot work
V-ing form
I cannot be working you cannot be working he cannot be working we cannot be working you cannot be working they cannot be working
Perfect
I cannot have worked you cannot have worked he cannot have worked we cannot have worked you cannot have worked they cannot have worked
V-ing perfect
I cannot have been working you cannot have been working he cannot have been working we cannot have been working you cannot have been working they cannot have been working
Interrogative form
Simple form
can I work? can you work? can he work? can we work? can you work? can they work?
V-ing form
can I be working? can you be working? can he be working? can we be working? can you be working? can they be working?
Perfect
can I have worked? can you have worked? can he have worked? can we have worked? can you have worked? can they have worked?
V-ing perfect
can I have been working? can you have been working? can he have been working? can we have been working? can you have been working? can they have been working?
Interro-negative form
Simple form
can I not work? can you not work? can he not work? can we not work? can you not work? can they not work?
V-ing form
can I not be working? can you not be working? can he not be working? can we not be working? can you not be working? can they not be working?
Perfect
can I not have worked? can you not have worked? can he not have worked? can we not have worked? can you not have worked? can they not have worked?
V-ing perfect
can I not have been working? can you not have been working? can he not have been working? can we not have been working? can you not have been working? can they not have been working?