I could injure you could injure he could injure we could injure you could injure they could injure
V-ing form
I could be injuring you could be injuring he could be injuring we could be injuring you could be injuring they could be injuring
Perfect
I could have injured you could have injured he could have injured we could have injured you could have injured they could have injured
V-ing perfect
I could have been injuring you could have been injuring he could have been injuring we could have been injuring you could have been injuring they could have been injuring
Negation
Simple form
I couldn't injure you couldn't injure he couldn't injure we couldn't injure you couldn't injure they couldn't injure
V-ing form
I couldn't be injuring you couldn't be injuring he couldn't be injuring we couldn't be injuring you couldn't be injuring they couldn't be injuring
Perfect
I couldn't have injured you couldn't have injured he couldn't have injured we couldn't have injured you couldn't have injured they couldn't have injured
V-ing perfect
I couldn't have been injuring you couldn't have been injuring he couldn't have been injuring we couldn't have been injuring you couldn't have been injuring they couldn't have been injuring
Interrogative form
Simple form
could I injure? could you injure? could he injure? could we injure? could you injure? could they injure?
V-ing form
could I be injuring? could you be injuring? could he be injuring? could we be injuring? could you be injuring? could they be injuring?
Perfect
could I have injured? could you have injured? could he have injured? could we have injured? could you have injured? could they have injured?
V-ing perfect
could I have been injuring? could you have been injuring? could he have been injuring? could we have been injuring? could you have been injuring? could they have been injuring?
Interro-negative form
Simple form
couldn't I injure? couldn't you injure? couldn't he injure? couldn't we injure? couldn't you injure? couldn't they injure?
V-ing form
couldn't I be injuring? couldn't you be injuring? couldn't he be injuring? couldn't we be injuring? couldn't you be injuring? couldn't they be injuring?
Perfect
couldn't I have injured? couldn't you have injured? couldn't he have injured? couldn't we have injured? couldn't you have injured? couldn't they have injured?
V-ing perfect
couldn't I have been injuring? couldn't you have been injuring? couldn't he have been injuring? couldn't we have been injuring? couldn't you have been injuring? couldn't they have been injuring?