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