English verb conjugation
COULD CALVE

Regular verb: calve - calved - calved

Affirmation

Simple form	V-ing form
I could calve you could calve he could calve we could calve you could calve they could calve	I could be calving you could be calving he could be calving we could be calving you could be calving they could be calving
Perfect	V-ing perfect
I could have calved you could have calved he could have calved we could have calved you could have calved they could have calved	I could have been calving you could have been calving he could have been calving we could have been calving you could have been calving they could have been calving

Negation

Simple form	V-ing form
I couldn't calve you couldn't calve he couldn't calve we couldn't calve you couldn't calve they couldn't calve	I couldn't be calving you couldn't be calving he couldn't be calving we couldn't be calving you couldn't be calving they couldn't be calving
Perfect	V-ing perfect
I couldn't have calved you couldn't have calved he couldn't have calved we couldn't have calved you couldn't have calved they couldn't have calved	I couldn't have been calving you couldn't have been calving he couldn't have been calving we couldn't have been calving you couldn't have been calving they couldn't have been calving

Interrogative form

Simple form	V-ing form
could I calve? could you calve? could he calve? could we calve? could you calve? could they calve?	could I be calving? could you be calving? could he be calving? could we be calving? could you be calving? could they be calving?
Perfect	V-ing perfect
could I have calved? could you have calved? could he have calved? could we have calved? could you have calved? could they have calved?	could I have been calving? could you have been calving? could he have been calving? could we have been calving? could you have been calving? could they have been calving?

Interro-negative form

Simple form	V-ing form
couldn't I calve? couldn't you calve? couldn't he calve? couldn't we calve? couldn't you calve? couldn't they calve?	couldn't I be calving? couldn't you be calving? couldn't he be calving? couldn't we be calving? couldn't you be calving? couldn't they be calving?
Perfect	V-ing perfect
couldn't I have calved? couldn't you have calved? couldn't he have calved? couldn't we have calved? couldn't you have calved? couldn't they have calved?	couldn't I have been calving? couldn't you have been calving? couldn't he have been calving? couldn't we have been calving? couldn't you have been calving? couldn't they have been calving?