I can unscrew you can unscrew he can unscrew we can unscrew you can unscrew they can unscrew
V-ing form
I can be unscrewing you can be unscrewing he can be unscrewing we can be unscrewing you can be unscrewing they can be unscrewing
Perfect
I can have unscrewed you can have unscrewed he can have unscrewed we can have unscrewed you can have unscrewed they can have unscrewed
V-ing perfect
I can have been unscrewing you can have been unscrewing he can have been unscrewing we can have been unscrewing you can have been unscrewing they can have been unscrewing
Negation
Simple form
I can't unscrew you can't unscrew he can't unscrew we can't unscrew you can't unscrew they can't unscrew
V-ing form
I can't be unscrewing you can't be unscrewing he can't be unscrewing we can't be unscrewing you can't be unscrewing they can't be unscrewing
Perfect
I can't have unscrewed you can't have unscrewed he can't have unscrewed we can't have unscrewed you can't have unscrewed they can't have unscrewed
V-ing perfect
I can't have been unscrewing you can't have been unscrewing he can't have been unscrewing we can't have been unscrewing you can't have been unscrewing they can't have been unscrewing
Interrogative form
Simple form
can I unscrew? can you unscrew? can he unscrew? can we unscrew? can you unscrew? can they unscrew?
V-ing form
can I be unscrewing? can you be unscrewing? can he be unscrewing? can we be unscrewing? can you be unscrewing? can they be unscrewing?
Perfect
can I have unscrewed? can you have unscrewed? can he have unscrewed? can we have unscrewed? can you have unscrewed? can they have unscrewed?
V-ing perfect
can I have been unscrewing? can you have been unscrewing? can he have been unscrewing? can we have been unscrewing? can you have been unscrewing? can they have been unscrewing?
Interro-negative form
Simple form
can't I unscrew? can't you unscrew? can't he unscrew? can't we unscrew? can't you unscrew? can't they unscrew?
V-ing form
can't I be unscrewing? can't you be unscrewing? can't he be unscrewing? can't we be unscrewing? can't you be unscrewing? can't they be unscrewing?
Perfect
can't I have unscrewed? can't you have unscrewed? can't he have unscrewed? can't we have unscrewed? can't you have unscrewed? can't they have unscrewed?
V-ing perfect
can't I have been unscrewing? can't you have been unscrewing? can't he have been unscrewing? can't we have been unscrewing? can't you have been unscrewing? can't they have been unscrewing?