English verb conjugation
COULD SINGLE

Regular verb: single - singled - singled

Affirmation

Simple form	V-ing form
I could single you could single she could single we could single you could single they could single	I could be singling you could be singling she could be singling we could be singling you could be singling they could be singling
Perfect	V-ing perfect
I could have singled you could have singled she could have singled we could have singled you could have singled they could have singled	I could have been singling you could have been singling she could have been singling we could have been singling you could have been singling they could have been singling

Negation

Simple form	V-ing form
I couldn't single you couldn't single she couldn't single we couldn't single you couldn't single they couldn't single	I couldn't be singling you couldn't be singling she couldn't be singling we couldn't be singling you couldn't be singling they couldn't be singling
Perfect	V-ing perfect
I couldn't have singled you couldn't have singled she couldn't have singled we couldn't have singled you couldn't have singled they couldn't have singled	I couldn't have been singling you couldn't have been singling she couldn't have been singling we couldn't have been singling you couldn't have been singling they couldn't have been singling

Interrogative form

Simple form	V-ing form
could I single? could you single? could she single? could we single? could you single? could they single?	could I be singling? could you be singling? could she be singling? could we be singling? could you be singling? could they be singling?
Perfect	V-ing perfect
could I have singled? could you have singled? could she have singled? could we have singled? could you have singled? could they have singled?	could I have been singling? could you have been singling? could she have been singling? could we have been singling? could you have been singling? could they have been singling?

Interro-negative form

Simple form	V-ing form
couldn't I single? couldn't you single? couldn't she single? couldn't we single? couldn't you single? couldn't they single?	couldn't I be singling? couldn't you be singling? couldn't she be singling? couldn't we be singling? couldn't you be singling? couldn't they be singling?
Perfect	V-ing perfect
couldn't I have singled? couldn't you have singled? couldn't she have singled? couldn't we have singled? couldn't you have singled? couldn't they have singled?	couldn't I have been singling? couldn't you have been singling? couldn't she have been singling? couldn't we have been singling? couldn't you have been singling? couldn't they have been singling?