I'd be underestimating you'd be underestimating she'd be underestimating we'd be underestimating you'd be underestimating they'd be underestimating
Perfect
I would've underestimated you would've underestimated she would've underestimated we would've underestimated you would've underestimated they would've underestimated
V-ing perfect
I would've been underestimating you would've been underestimating she would've been underestimating we would've been underestimating you would've been underestimating they would've been underestimating
Negation
Simple form
I wouldn't underestimate you wouldn't underestimate she wouldn't underestimate we wouldn't underestimate you wouldn't underestimate they wouldn't underestimate
V-ing form
I wouldn't be underestimating you wouldn't be underestimating she wouldn't be underestimating we wouldn't be underestimating you wouldn't be underestimating they wouldn't be underestimating
Perfect
I wouldn't have underestimated you wouldn't have underestimated she wouldn't have underestimated we wouldn't have underestimated you wouldn't have underestimated they wouldn't have underestimated
V-ing perfect
I wouldn't have been underestimating you wouldn't have been underestimating she wouldn't have been underestimating we wouldn't have been underestimating you wouldn't have been underestimating they wouldn't have been underestimating
Interrogative form
Simple form
would I underestimate? would you underestimate? would she underestimate? would we underestimate? would you underestimate? would they underestimate?
V-ing form
would I be underestimating? would you be underestimating? would she be underestimating? would we be underestimating? would you be underestimating? would they be underestimating?
Perfect
would I have underestimated? would you have underestimated? would she have underestimated? would we have underestimated? would you have underestimated? would they have underestimated?
V-ing perfect
would I have been underestimating? would you have been underestimating? would she have been underestimating? would we have been underestimating? would you have been underestimating? would they have been underestimating?
Interro-negative form
Simple form
wouldn't I underestimate? wouldn't you underestimate? wouldn't she underestimate? wouldn't we underestimate? wouldn't you underestimate? wouldn't they underestimate?
V-ing form
wouldn't I be underestimating? wouldn't you be underestimating? wouldn't she be underestimating? wouldn't we be underestimating? wouldn't you be underestimating? wouldn't they be underestimating?
Perfect
wouldn't I have underestimated? wouldn't you have underestimated? wouldn't she have underestimated? wouldn't we have underestimated? wouldn't you have underestimated? wouldn't they have underestimated?
V-ing perfect
wouldn't I have been underestimating? wouldn't you have been underestimating? wouldn't she have been underestimating? wouldn't we have been underestimating? wouldn't you have been underestimating? wouldn't they have been underestimating?