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