English verb conjugation
COULD OPPUGN

Regular verb: oppugn - oppugned - oppugned

Affirmation

Simple form	V-ing form
I could oppugn you could oppugn he could oppugn we could oppugn you could oppugn they could oppugn	I could be oppugning you could be oppugning he could be oppugning we could be oppugning you could be oppugning they could be oppugning
Perfect	V-ing perfect
I could have oppugned you could have oppugned he could have oppugned we could have oppugned you could have oppugned they could have oppugned	I could have been oppugning you could have been oppugning he could have been oppugning we could have been oppugning you could have been oppugning they could have been oppugning

Negation

Simple form	V-ing form
I couldn't oppugn you couldn't oppugn he couldn't oppugn we couldn't oppugn you couldn't oppugn they couldn't oppugn	I couldn't be oppugning you couldn't be oppugning he couldn't be oppugning we couldn't be oppugning you couldn't be oppugning they couldn't be oppugning
Perfect	V-ing perfect
I couldn't have oppugned you couldn't have oppugned he couldn't have oppugned we couldn't have oppugned you couldn't have oppugned they couldn't have oppugned	I couldn't have been oppugning you couldn't have been oppugning he couldn't have been oppugning we couldn't have been oppugning you couldn't have been oppugning they couldn't have been oppugning

Interrogative form

Simple form	V-ing form
could I oppugn? could you oppugn? could he oppugn? could we oppugn? could you oppugn? could they oppugn?	could I be oppugning? could you be oppugning? could he be oppugning? could we be oppugning? could you be oppugning? could they be oppugning?
Perfect	V-ing perfect
could I have oppugned? could you have oppugned? could he have oppugned? could we have oppugned? could you have oppugned? could they have oppugned?	could I have been oppugning? could you have been oppugning? could he have been oppugning? could we have been oppugning? could you have been oppugning? could they have been oppugning?

Interro-negative form

Simple form	V-ing form
couldn't I oppugn? couldn't you oppugn? couldn't he oppugn? couldn't we oppugn? couldn't you oppugn? couldn't they oppugn?	couldn't I be oppugning? couldn't you be oppugning? couldn't he be oppugning? couldn't we be oppugning? couldn't you be oppugning? couldn't they be oppugning?
Perfect	V-ing perfect
couldn't I have oppugned? couldn't you have oppugned? couldn't he have oppugned? couldn't we have oppugned? couldn't you have oppugned? couldn't they have oppugned?	couldn't I have been oppugning? couldn't you have been oppugning? couldn't he have been oppugning? couldn't we have been oppugning? couldn't you have been oppugning? couldn't they have been oppugning?