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