English verb conjugation
COULD PLONK

Regular verb: plonk - plonked - plonked

Affirmation

Simple form	V-ing form
I could plonk you could plonk he could plonk we could plonk you could plonk they could plonk	I could be plonking you could be plonking he could be plonking we could be plonking you could be plonking they could be plonking
Perfect	V-ing perfect
I could have plonked you could have plonked he could have plonked we could have plonked you could have plonked they could have plonked	I could have been plonking you could have been plonking he could have been plonking we could have been plonking you could have been plonking they could have been plonking

Negation

Simple form	V-ing form
I couldn't plonk you couldn't plonk he couldn't plonk we couldn't plonk you couldn't plonk they couldn't plonk	I couldn't be plonking you couldn't be plonking he couldn't be plonking we couldn't be plonking you couldn't be plonking they couldn't be plonking
Perfect	V-ing perfect
I couldn't have plonked you couldn't have plonked he couldn't have plonked we couldn't have plonked you couldn't have plonked they couldn't have plonked	I couldn't have been plonking you couldn't have been plonking he couldn't have been plonking we couldn't have been plonking you couldn't have been plonking they couldn't have been plonking

Interrogative form

Simple form	V-ing form
could I plonk? could you plonk? could he plonk? could we plonk? could you plonk? could they plonk?	could I be plonking? could you be plonking? could he be plonking? could we be plonking? could you be plonking? could they be plonking?
Perfect	V-ing perfect
could I have plonked? could you have plonked? could he have plonked? could we have plonked? could you have plonked? could they have plonked?	could I have been plonking? could you have been plonking? could he have been plonking? could we have been plonking? could you have been plonking? could they have been plonking?

Interro-negative form

Simple form	V-ing form
couldn't I plonk? couldn't you plonk? couldn't he plonk? couldn't we plonk? couldn't you plonk? couldn't they plonk?	couldn't I be plonking? couldn't you be plonking? couldn't he be plonking? couldn't we be plonking? couldn't you be plonking? couldn't they be plonking?
Perfect	V-ing perfect
couldn't I have plonked? couldn't you have plonked? couldn't he have plonked? couldn't we have plonked? couldn't you have plonked? couldn't they have plonked?	couldn't I have been plonking? couldn't you have been plonking? couldn't he have been plonking? couldn't we have been plonking? couldn't you have been plonking? couldn't they have been plonking?