I could evaluate you could evaluate she could evaluate we could evaluate you could evaluate they could evaluate
V-ing form
I could be evaluating you could be evaluating she could be evaluating we could be evaluating you could be evaluating they could be evaluating
Perfect
I could have evaluated you could have evaluated she 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 she 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 she 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 she 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 she 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 she 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 she evaluate? could we evaluate? could you evaluate? could they evaluate?
V-ing form
could I be evaluating? could you be evaluating? could she be evaluating? could we be evaluating? could you be evaluating? could they be evaluating?
Perfect
could I have evaluated? could you have evaluated? could she 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 she 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 she 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 she 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 she 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 she have been evaluating? couldn't we have been evaluating? couldn't you have been evaluating? couldn't they have been evaluating?