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