English verb conjugation
COULD SHRILL

Regular verb: shrill - shrilled - shrilled

Affirmation

Simple form	V-ing form
I could shrill you could shrill she could shrill we could shrill you could shrill they could shrill	I could be shrilling you could be shrilling she could be shrilling we could be shrilling you could be shrilling they could be shrilling
Perfect	V-ing perfect
I could have shrilled you could have shrilled she could have shrilled we could have shrilled you could have shrilled they could have shrilled	I could have been shrilling you could have been shrilling she could have been shrilling we could have been shrilling you could have been shrilling they could have been shrilling

Negation

Simple form	V-ing form
I couldn't shrill you couldn't shrill she couldn't shrill we couldn't shrill you couldn't shrill they couldn't shrill	I couldn't be shrilling you couldn't be shrilling she couldn't be shrilling we couldn't be shrilling you couldn't be shrilling they couldn't be shrilling
Perfect	V-ing perfect
I couldn't have shrilled you couldn't have shrilled she couldn't have shrilled we couldn't have shrilled you couldn't have shrilled they couldn't have shrilled	I couldn't have been shrilling you couldn't have been shrilling she couldn't have been shrilling we couldn't have been shrilling you couldn't have been shrilling they couldn't have been shrilling

Interrogative form

Simple form	V-ing form
could I shrill? could you shrill? could she shrill? could we shrill? could you shrill? could they shrill?	could I be shrilling? could you be shrilling? could she be shrilling? could we be shrilling? could you be shrilling? could they be shrilling?
Perfect	V-ing perfect
could I have shrilled? could you have shrilled? could she have shrilled? could we have shrilled? could you have shrilled? could they have shrilled?	could I have been shrilling? could you have been shrilling? could she have been shrilling? could we have been shrilling? could you have been shrilling? could they have been shrilling?

Interro-negative form

Simple form	V-ing form
couldn't I shrill? couldn't you shrill? couldn't she shrill? couldn't we shrill? couldn't you shrill? couldn't they shrill?	couldn't I be shrilling? couldn't you be shrilling? couldn't she be shrilling? couldn't we be shrilling? couldn't you be shrilling? couldn't they be shrilling?
Perfect	V-ing perfect
couldn't I have shrilled? couldn't you have shrilled? couldn't she have shrilled? couldn't we have shrilled? couldn't you have shrilled? couldn't they have shrilled?	couldn't I have been shrilling? couldn't you have been shrilling? couldn't she have been shrilling? couldn't we have been shrilling? couldn't you have been shrilling? couldn't they have been shrilling?