I could liven you could liven he could liven we could liven you could liven they could liven
V-ing form
I could be livening you could be livening he could be livening we could be livening you could be livening they could be livening
Perfect
I could have livened you could have livened he could have livened we could have livened you could have livened they could have livened
V-ing perfect
I could have been livening you could have been livening he could have been livening we could have been livening you could have been livening they could have been livening
Negation
Simple form
I could not liven you could not liven he could not liven we could not liven you could not liven they could not liven
V-ing form
I could not be livening you could not be livening he could not be livening we could not be livening you could not be livening they could not be livening
Perfect
I could not have livened you could not have livened he could not have livened we could not have livened you could not have livened they could not have livened
V-ing perfect
I could not have been livening you could not have been livening he could not have been livening we could not have been livening you could not have been livening they could not have been livening
Interrogative form
Simple form
could I liven? could you liven? could he liven? could we liven? could you liven? could they liven?
V-ing form
could I be livening? could you be livening? could he be livening? could we be livening? could you be livening? could they be livening?
Perfect
could I have livened? could you have livened? could he have livened? could we have livened? could you have livened? could they have livened?
V-ing perfect
could I have been livening? could you have been livening? could he have been livening? could we have been livening? could you have been livening? could they have been livening?
Interro-negative form
Simple form
could I not liven? could you not liven? could he not liven? could we not liven? could you not liven? could they not liven?
V-ing form
could I not be livening? could you not be livening? could he not be livening? could we not be livening? could you not be livening? could they not be livening?
Perfect
could I not have livened? could you not have livened? could he not have livened? could we not have livened? could you not have livened? could they not have livened?
V-ing perfect
could I not have been livening? could you not have been livening? could he not have been livening? could we not have been livening? could you not have been livening? could they not have been livening?