English verb conjugation
COULD CO-STAR

Regular verb: co-star - co-stared - co-stared

Affirmation

Simple form	V-ing form
I could co-star you could co-star he could co-star we could co-star you could co-star they could co-star	I could be co-staring you could be co-staring he could be co-staring we could be co-staring you could be co-staring they could be co-staring
Perfect	V-ing perfect
I could have co-stared you could have co-stared he could have co-stared we could have co-stared you could have co-stared they could have co-stared	I could have been co-staring you could have been co-staring he could have been co-staring we could have been co-staring you could have been co-staring they could have been co-staring

Negation

Simple form	V-ing form
I couldn't co-star you couldn't co-star he couldn't co-star we couldn't co-star you couldn't co-star they couldn't co-star	I couldn't be co-staring you couldn't be co-staring he couldn't be co-staring we couldn't be co-staring you couldn't be co-staring they couldn't be co-staring
Perfect	V-ing perfect
I couldn't have co-stared you couldn't have co-stared he couldn't have co-stared we couldn't have co-stared you couldn't have co-stared they couldn't have co-stared	I couldn't have been co-staring you couldn't have been co-staring he couldn't have been co-staring we couldn't have been co-staring you couldn't have been co-staring they couldn't have been co-staring

Interrogative form

Simple form	V-ing form
could I co-star? could you co-star? could he co-star? could we co-star? could you co-star? could they co-star?	could I be co-staring? could you be co-staring? could he be co-staring? could we be co-staring? could you be co-staring? could they be co-staring?
Perfect	V-ing perfect
could I have co-stared? could you have co-stared? could he have co-stared? could we have co-stared? could you have co-stared? could they have co-stared?	could I have been co-staring? could you have been co-staring? could he have been co-staring? could we have been co-staring? could you have been co-staring? could they have been co-staring?

Interro-negative form

Simple form	V-ing form
couldn't I co-star? couldn't you co-star? couldn't he co-star? couldn't we co-star? couldn't you co-star? couldn't they co-star?	couldn't I be co-staring? couldn't you be co-staring? couldn't he be co-staring? couldn't we be co-staring? couldn't you be co-staring? couldn't they be co-staring?
Perfect	V-ing perfect
couldn't I have co-stared? couldn't you have co-stared? couldn't he have co-stared? couldn't we have co-stared? couldn't you have co-stared? couldn't they have co-stared?	couldn't I have been co-staring? couldn't you have been co-staring? couldn't he have been co-staring? couldn't we have been co-staring? couldn't you have been co-staring? couldn't they have been co-staring?