English verb conjugation
COULD CHALK

Regular verb: chalk - chalked - chalked

Affirmation

Simple form	V-ing form
I could chalk you could chalk she could chalk we could chalk you could chalk they could chalk	I could be chalking you could be chalking she could be chalking we could be chalking you could be chalking they could be chalking
Perfect	V-ing perfect
I could have chalked you could have chalked she could have chalked we could have chalked you could have chalked they could have chalked	I could have been chalking you could have been chalking she could have been chalking we could have been chalking you could have been chalking they could have been chalking

Negation

Simple form	V-ing form
I could not chalk you could not chalk she could not chalk we could not chalk you could not chalk they could not chalk	I could not be chalking you could not be chalking she could not be chalking we could not be chalking you could not be chalking they could not be chalking
Perfect	V-ing perfect
I could not have chalked you could not have chalked she could not have chalked we could not have chalked you could not have chalked they could not have chalked	I could not have been chalking you could not have been chalking she could not have been chalking we could not have been chalking you could not have been chalking they could not have been chalking

Interrogative form

Simple form	V-ing form
could I chalk? could you chalk? could she chalk? could we chalk? could you chalk? could they chalk?	could I be chalking? could you be chalking? could she be chalking? could we be chalking? could you be chalking? could they be chalking?
Perfect	V-ing perfect
could I have chalked? could you have chalked? could she have chalked? could we have chalked? could you have chalked? could they have chalked?	could I have been chalking? could you have been chalking? could she have been chalking? could we have been chalking? could you have been chalking? could they have been chalking?

Interro-negative form

Simple form	V-ing form
could I not chalk? could you not chalk? could she not chalk? could we not chalk? could you not chalk? could they not chalk?	could I not be chalking? could you not be chalking? could she not be chalking? could we not be chalking? could you not be chalking? could they not be chalking?
Perfect	V-ing perfect
could I not have chalked? could you not have chalked? could she not have chalked? could we not have chalked? could you not have chalked? could they not have chalked?	could I not have been chalking? could you not have been chalking? could she not have been chalking? could we not have been chalking? could you not have been chalking? could they not have been chalking?