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