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