English verb conjugation
COULD CHAIR

Regular verb: chair - chaired - chaired

Affirmation

Simple form	V-ing form
I could chair you could chair he could chair we could chair you could chair they could chair	I could be chairing you could be chairing he could be chairing we could be chairing you could be chairing they could be chairing
Perfect	V-ing perfect
I could have chaired you could have chaired he could have chaired we could have chaired you could have chaired they could have chaired	I could have been chairing you could have been chairing he could have been chairing we could have been chairing you could have been chairing they could have been chairing

Negation

Simple form	V-ing form
I couldn't chair you couldn't chair he couldn't chair we couldn't chair you couldn't chair they couldn't chair	I couldn't be chairing you couldn't be chairing he couldn't be chairing we couldn't be chairing you couldn't be chairing they couldn't be chairing
Perfect	V-ing perfect
I couldn't have chaired you couldn't have chaired he couldn't have chaired we couldn't have chaired you couldn't have chaired they couldn't have chaired	I couldn't have been chairing you couldn't have been chairing he couldn't have been chairing we couldn't have been chairing you couldn't have been chairing they couldn't have been chairing

Interrogative form

Simple form	V-ing form
could I chair? could you chair? could he chair? could we chair? could you chair? could they chair?	could I be chairing? could you be chairing? could he be chairing? could we be chairing? could you be chairing? could they be chairing?
Perfect	V-ing perfect
could I have chaired? could you have chaired? could he have chaired? could we have chaired? could you have chaired? could they have chaired?	could I have been chairing? could you have been chairing? could he have been chairing? could we have been chairing? could you have been chairing? could they have been chairing?

Interro-negative form

Simple form	V-ing form
couldn't I chair? couldn't you chair? couldn't he chair? couldn't we chair? couldn't you chair? couldn't they chair?	couldn't I be chairing? couldn't you be chairing? couldn't he be chairing? couldn't we be chairing? couldn't you be chairing? couldn't they be chairing?
Perfect	V-ing perfect
couldn't I have chaired? couldn't you have chaired? couldn't he have chaired? couldn't we have chaired? couldn't you have chaired? couldn't they have chaired?	couldn't I have been chairing? couldn't you have been chairing? couldn't he have been chairing? couldn't we have been chairing? couldn't you have been chairing? couldn't they have been chairing?