English verb conjugation
COULD BILLBOARD

Regular verb: billboard - billboarded - billboarded

Affirmation

Simple form	V-ing form
I could billboard you could billboard he could billboard we could billboard you could billboard they could billboard	I could be billboarding you could be billboarding he could be billboarding we could be billboarding you could be billboarding they could be billboarding
Perfect	V-ing perfect
I could have billboarded you could have billboarded he could have billboarded we could have billboarded you could have billboarded they could have billboarded	I could have been billboarding you could have been billboarding he could have been billboarding we could have been billboarding you could have been billboarding they could have been billboarding

Negation

Simple form	V-ing form
I couldn't billboard you couldn't billboard he couldn't billboard we couldn't billboard you couldn't billboard they couldn't billboard	I couldn't be billboarding you couldn't be billboarding he couldn't be billboarding we couldn't be billboarding you couldn't be billboarding they couldn't be billboarding
Perfect	V-ing perfect
I couldn't have billboarded you couldn't have billboarded he couldn't have billboarded we couldn't have billboarded you couldn't have billboarded they couldn't have billboarded	I couldn't have been billboarding you couldn't have been billboarding he couldn't have been billboarding we couldn't have been billboarding you couldn't have been billboarding they couldn't have been billboarding

Interrogative form

Simple form	V-ing form
could I billboard? could you billboard? could he billboard? could we billboard? could you billboard? could they billboard?	could I be billboarding? could you be billboarding? could he be billboarding? could we be billboarding? could you be billboarding? could they be billboarding?
Perfect	V-ing perfect
could I have billboarded? could you have billboarded? could he have billboarded? could we have billboarded? could you have billboarded? could they have billboarded?	could I have been billboarding? could you have been billboarding? could he have been billboarding? could we have been billboarding? could you have been billboarding? could they have been billboarding?

Interro-negative form

Simple form	V-ing form
couldn't I billboard? couldn't you billboard? couldn't he billboard? couldn't we billboard? couldn't you billboard? couldn't they billboard?	couldn't I be billboarding? couldn't you be billboarding? couldn't he be billboarding? couldn't we be billboarding? couldn't you be billboarding? couldn't they be billboarding?
Perfect	V-ing perfect
couldn't I have billboarded? couldn't you have billboarded? couldn't he have billboarded? couldn't we have billboarded? couldn't you have billboarded? couldn't they have billboarded?	couldn't I have been billboarding? couldn't you have been billboarding? couldn't he have been billboarding? couldn't we have been billboarding? couldn't you have been billboarding? couldn't they have been billboarding?