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