English verb conjugation
COULD SINGE

Regular verb: singe - singed - singed

Affirmation

Simple form	V-ing form
I could singe you could singe she could singe we could singe you could singe they could singe	I could be singing you could be singing she could be singing we could be singing you could be singing they could be singing
Perfect	V-ing perfect
I could have singed you could have singed she could have singed we could have singed you could have singed they could have singed	I could have been singing you could have been singing she could have been singing we could have been singing you could have been singing they could have been singing

Negation

Simple form	V-ing form
I could not singe you could not singe she could not singe we could not singe you could not singe they could not singe	I could not be singing you could not be singing she could not be singing we could not be singing you could not be singing they could not be singing
Perfect	V-ing perfect
I could not have singed you could not have singed she could not have singed we could not have singed you could not have singed they could not have singed	I could not have been singing you could not have been singing she could not have been singing we could not have been singing you could not have been singing they could not have been singing

Interrogative form

Simple form	V-ing form
could I singe? could you singe? could she singe? could we singe? could you singe? could they singe?	could I be singing? could you be singing? could she be singing? could we be singing? could you be singing? could they be singing?
Perfect	V-ing perfect
could I have singed? could you have singed? could she have singed? could we have singed? could you have singed? could they have singed?	could I have been singing? could you have been singing? could she have been singing? could we have been singing? could you have been singing? could they have been singing?

Interro-negative form

Simple form	V-ing form
could I not singe? could you not singe? could she not singe? could we not singe? could you not singe? could they not singe?	could I not be singing? could you not be singing? could she not be singing? could we not be singing? could you not be singing? could they not be singing?
Perfect	V-ing perfect
could I not have singed? could you not have singed? could she not have singed? could we not have singed? could you not have singed? could they not have singed?	could I not have been singing? could you not have been singing? could she not have been singing? could we not have been singing? could you not have been singing? could they not have been singing?