I could ad-lib you could ad-lib she could ad-lib we could ad-lib you could ad-lib they could ad-lib
V-ing form
I could be ad-libing you could be ad-libing she could be ad-libing we could be ad-libing you could be ad-libing they could be ad-libing
Perfect
I could have ad-libed you could have ad-libed she could have ad-libed we could have ad-libed you could have ad-libed they could have ad-libed
V-ing perfect
I could have been ad-libing you could have been ad-libing she could have been ad-libing we could have been ad-libing you could have been ad-libing they could have been ad-libing
Negation
Simple form
I could not ad-lib you could not ad-lib she could not ad-lib we could not ad-lib you could not ad-lib they could not ad-lib
V-ing form
I could not be ad-libing you could not be ad-libing she could not be ad-libing we could not be ad-libing you could not be ad-libing they could not be ad-libing
Perfect
I could not have ad-libed you could not have ad-libed she could not have ad-libed we could not have ad-libed you could not have ad-libed they could not have ad-libed
V-ing perfect
I could not have been ad-libing you could not have been ad-libing she could not have been ad-libing we could not have been ad-libing you could not have been ad-libing they could not have been ad-libing
Interrogative form
Simple form
could I ad-lib? could you ad-lib? could she ad-lib? could we ad-lib? could you ad-lib? could they ad-lib?
V-ing form
could I be ad-libing? could you be ad-libing? could she be ad-libing? could we be ad-libing? could you be ad-libing? could they be ad-libing?
Perfect
could I have ad-libed? could you have ad-libed? could she have ad-libed? could we have ad-libed? could you have ad-libed? could they have ad-libed?
V-ing perfect
could I have been ad-libing? could you have been ad-libing? could she have been ad-libing? could we have been ad-libing? could you have been ad-libing? could they have been ad-libing?
Interro-negative form
Simple form
could I not ad-lib? could you not ad-lib? could she not ad-lib? could we not ad-lib? could you not ad-lib? could they not ad-lib?
V-ing form
could I not be ad-libing? could you not be ad-libing? could she not be ad-libing? could we not be ad-libing? could you not be ad-libing? could they not be ad-libing?
Perfect
could I not have ad-libed? could you not have ad-libed? could she not have ad-libed? could we not have ad-libed? could you not have ad-libed? could they not have ad-libed?
V-ing perfect
could I not have been ad-libing? could you not have been ad-libing? could she not have been ad-libing? could we not have been ad-libing? could you not have been ad-libing? could they not have been ad-libing?