I can test you can test he can test we can test you can test they can test
V-ing form
I can be testing you can be testing he can be testing we can be testing you can be testing they can be testing
Perfect
I can have tested you can have tested he can have tested we can have tested you can have tested they can have tested
V-ing perfect
I can have been testing you can have been testing he can have been testing we can have been testing you can have been testing they can have been testing
Negation
Simple form
I can't test you can't test he can't test we can't test you can't test they can't test
V-ing form
I can't be testing you can't be testing he can't be testing we can't be testing you can't be testing they can't be testing
Perfect
I can't have tested you can't have tested he can't have tested we can't have tested you can't have tested they can't have tested
V-ing perfect
I can't have been testing you can't have been testing he can't have been testing we can't have been testing you can't have been testing they can't have been testing
Interrogative form
Simple form
can I test? can you test? can he test? can we test? can you test? can they test?
V-ing form
can I be testing? can you be testing? can he be testing? can we be testing? can you be testing? can they be testing?
Perfect
can I have tested? can you have tested? can he have tested? can we have tested? can you have tested? can they have tested?
V-ing perfect
can I have been testing? can you have been testing? can he have been testing? can we have been testing? can you have been testing? can they have been testing?
Interro-negative form
Simple form
can't I test? can't you test? can't he test? can't we test? can't you test? can't they test?
V-ing form
can't I be testing? can't you be testing? can't he be testing? can't we be testing? can't you be testing? can't they be testing?
Perfect
can't I have tested? can't you have tested? can't he have tested? can't we have tested? can't you have tested? can't they have tested?
V-ing perfect
can't I have been testing? can't you have been testing? can't he have been testing? can't we have been testing? can't you have been testing? can't they have been testing?