English verb conjugation
COULD SHIRR

Regular verb: shirr - shirred - shirred

Affirmation

Simple form	V-ing form
I could shirr you could shirr he could shirr we could shirr you could shirr they could shirr	I could be shirring you could be shirring he could be shirring we could be shirring you could be shirring they could be shirring
Perfect	V-ing perfect
I could have shirred you could have shirred he could have shirred we could have shirred you could have shirred they could have shirred	I could have been shirring you could have been shirring he could have been shirring we could have been shirring you could have been shirring they could have been shirring

Negation

Simple form	V-ing form
I couldn't shirr you couldn't shirr he couldn't shirr we couldn't shirr you couldn't shirr they couldn't shirr	I couldn't be shirring you couldn't be shirring he couldn't be shirring we couldn't be shirring you couldn't be shirring they couldn't be shirring
Perfect	V-ing perfect
I couldn't have shirred you couldn't have shirred he couldn't have shirred we couldn't have shirred you couldn't have shirred they couldn't have shirred	I couldn't have been shirring you couldn't have been shirring he couldn't have been shirring we couldn't have been shirring you couldn't have been shirring they couldn't have been shirring

Interrogative form

Simple form	V-ing form
could I shirr? could you shirr? could he shirr? could we shirr? could you shirr? could they shirr?	could I be shirring? could you be shirring? could he be shirring? could we be shirring? could you be shirring? could they be shirring?
Perfect	V-ing perfect
could I have shirred? could you have shirred? could he have shirred? could we have shirred? could you have shirred? could they have shirred?	could I have been shirring? could you have been shirring? could he have been shirring? could we have been shirring? could you have been shirring? could they have been shirring?

Interro-negative form

Simple form	V-ing form
couldn't I shirr? couldn't you shirr? couldn't he shirr? couldn't we shirr? couldn't you shirr? couldn't they shirr?	couldn't I be shirring? couldn't you be shirring? couldn't he be shirring? couldn't we be shirring? couldn't you be shirring? couldn't they be shirring?
Perfect	V-ing perfect
couldn't I have shirred? couldn't you have shirred? couldn't he have shirred? couldn't we have shirred? couldn't you have shirred? couldn't they have shirred?	couldn't I have been shirring? couldn't you have been shirring? couldn't he have been shirring? couldn't we have been shirring? couldn't you have been shirring? couldn't they have been shirring?