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