English verb conjugation
COULD BUSK

Regular verb: busk - busked - busked

Affirmation

Simple form	V-ing form
I could busk you could busk he could busk we could busk you could busk they could busk	I could be busking you could be busking he could be busking we could be busking you could be busking they could be busking
Perfect	V-ing perfect
I could have busked you could have busked he could have busked we could have busked you could have busked they could have busked	I could have been busking you could have been busking he could have been busking we could have been busking you could have been busking they could have been busking

Negation

Simple form	V-ing form
I couldn't busk you couldn't busk he couldn't busk we couldn't busk you couldn't busk they couldn't busk	I couldn't be busking you couldn't be busking he couldn't be busking we couldn't be busking you couldn't be busking they couldn't be busking
Perfect	V-ing perfect
I couldn't have busked you couldn't have busked he couldn't have busked we couldn't have busked you couldn't have busked they couldn't have busked	I couldn't have been busking you couldn't have been busking he couldn't have been busking we couldn't have been busking you couldn't have been busking they couldn't have been busking

Interrogative form

Simple form	V-ing form
could I busk? could you busk? could he busk? could we busk? could you busk? could they busk?	could I be busking? could you be busking? could he be busking? could we be busking? could you be busking? could they be busking?
Perfect	V-ing perfect
could I have busked? could you have busked? could he have busked? could we have busked? could you have busked? could they have busked?	could I have been busking? could you have been busking? could he have been busking? could we have been busking? could you have been busking? could they have been busking?

Interro-negative form

Simple form	V-ing form
couldn't I busk? couldn't you busk? couldn't he busk? couldn't we busk? couldn't you busk? couldn't they busk?	couldn't I be busking? couldn't you be busking? couldn't he be busking? couldn't we be busking? couldn't you be busking? couldn't they be busking?
Perfect	V-ing perfect
couldn't I have busked? couldn't you have busked? couldn't he have busked? couldn't we have busked? couldn't you have busked? couldn't they have busked?	couldn't I have been busking? couldn't you have been busking? couldn't he have been busking? couldn't we have been busking? couldn't you have been busking? couldn't they have been busking?