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