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