I could package you could package she could package we could package you could package they could package
V-ing form
I could be packaging you could be packaging she could be packaging we could be packaging you could be packaging they could be packaging
Perfect
I could have packaged you could have packaged she 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 she 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 she 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 she 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 she 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 she 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 she package? could we package? could you package? could they package?
V-ing form
could I be packaging? could you be packaging? could she be packaging? could we be packaging? could you be packaging? could they be packaging?
Perfect
could I have packaged? could you have packaged? could she 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 she 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 she 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 she 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 she 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 she have been packaging? couldn't we have been packaging? couldn't you have been packaging? couldn't they have been packaging?