English verb conjugation
COULD CALK

Regular verb: calk - calked - calked

Affirmation

Simple form	V-ing form
I could calk you could calk he could calk we could calk you could calk they could calk	I could be calking you could be calking he could be calking we could be calking you could be calking they could be calking
Perfect	V-ing perfect
I could have calked you could have calked he could have calked we could have calked you could have calked they could have calked	I could have been calking you could have been calking he could have been calking we could have been calking you could have been calking they could have been calking

Negation

Simple form	V-ing form
I couldn't calk you couldn't calk he couldn't calk we couldn't calk you couldn't calk they couldn't calk	I couldn't be calking you couldn't be calking he couldn't be calking we couldn't be calking you couldn't be calking they couldn't be calking
Perfect	V-ing perfect
I couldn't have calked you couldn't have calked he couldn't have calked we couldn't have calked you couldn't have calked they couldn't have calked	I couldn't have been calking you couldn't have been calking he couldn't have been calking we couldn't have been calking you couldn't have been calking they couldn't have been calking

Interrogative form

Simple form	V-ing form
could I calk? could you calk? could he calk? could we calk? could you calk? could they calk?	could I be calking? could you be calking? could he be calking? could we be calking? could you be calking? could they be calking?
Perfect	V-ing perfect
could I have calked? could you have calked? could he have calked? could we have calked? could you have calked? could they have calked?	could I have been calking? could you have been calking? could he have been calking? could we have been calking? could you have been calking? could they have been calking?

Interro-negative form

Simple form	V-ing form
couldn't I calk? couldn't you calk? couldn't he calk? couldn't we calk? couldn't you calk? couldn't they calk?	couldn't I be calking? couldn't you be calking? couldn't he be calking? couldn't we be calking? couldn't you be calking? couldn't they be calking?
Perfect	V-ing perfect
couldn't I have calked? couldn't you have calked? couldn't he have calked? couldn't we have calked? couldn't you have calked? couldn't they have calked?	couldn't I have been calking? couldn't you have been calking? couldn't he have been calking? couldn't we have been calking? couldn't you have been calking? couldn't they have been calking?