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