English verb conjugation
COULD SPRAIN

Regular verb: sprain - sprained - sprained

Affirmation

Simple form	V-ing form
I could sprain you could sprain she could sprain we could sprain you could sprain they could sprain	I could be spraining you could be spraining she could be spraining we could be spraining you could be spraining they could be spraining
Perfect	V-ing perfect
I could have sprained you could have sprained she could have sprained we could have sprained you could have sprained they could have sprained	I could have been spraining you could have been spraining she could have been spraining we could have been spraining you could have been spraining they could have been spraining

Negation

Simple form	V-ing form
I couldn't sprain you couldn't sprain she couldn't sprain we couldn't sprain you couldn't sprain they couldn't sprain	I couldn't be spraining you couldn't be spraining she couldn't be spraining we couldn't be spraining you couldn't be spraining they couldn't be spraining
Perfect	V-ing perfect
I couldn't have sprained you couldn't have sprained she couldn't have sprained we couldn't have sprained you couldn't have sprained they couldn't have sprained	I couldn't have been spraining you couldn't have been spraining she couldn't have been spraining we couldn't have been spraining you couldn't have been spraining they couldn't have been spraining

Interrogative form

Simple form	V-ing form
could I sprain? could you sprain? could she sprain? could we sprain? could you sprain? could they sprain?	could I be spraining? could you be spraining? could she be spraining? could we be spraining? could you be spraining? could they be spraining?
Perfect	V-ing perfect
could I have sprained? could you have sprained? could she have sprained? could we have sprained? could you have sprained? could they have sprained?	could I have been spraining? could you have been spraining? could she have been spraining? could we have been spraining? could you have been spraining? could they have been spraining?

Interro-negative form

Simple form	V-ing form
couldn't I sprain? couldn't you sprain? couldn't she sprain? couldn't we sprain? couldn't you sprain? couldn't they sprain?	couldn't I be spraining? couldn't you be spraining? couldn't she be spraining? couldn't we be spraining? couldn't you be spraining? couldn't they be spraining?
Perfect	V-ing perfect
couldn't I have sprained? couldn't you have sprained? couldn't she have sprained? couldn't we have sprained? couldn't you have sprained? couldn't they have sprained?	couldn't I have been spraining? couldn't you have been spraining? couldn't she have been spraining? couldn't we have been spraining? couldn't you have been spraining? couldn't they have been spraining?