I could recertify you could recertify she could recertify we could recertify you could recertify they could recertify
V-ing form
I could be recertifying you could be recertifying she could be recertifying we could be recertifying you could be recertifying they could be recertifying
Perfect
I could have recertified you could have recertified she could have recertified we could have recertified you could have recertified they could have recertified
V-ing perfect
I could have been recertifying you could have been recertifying she could have been recertifying we could have been recertifying you could have been recertifying they could have been recertifying
Negation
Simple form
I could not recertify you could not recertify she could not recertify we could not recertify you could not recertify they could not recertify
V-ing form
I could not be recertifying you could not be recertifying she could not be recertifying we could not be recertifying you could not be recertifying they could not be recertifying
Perfect
I could not have recertified you could not have recertified she could not have recertified we could not have recertified you could not have recertified they could not have recertified
V-ing perfect
I could not have been recertifying you could not have been recertifying she could not have been recertifying we could not have been recertifying you could not have been recertifying they could not have been recertifying
Interrogative form
Simple form
could I recertify? could you recertify? could she recertify? could we recertify? could you recertify? could they recertify?
V-ing form
could I be recertifying? could you be recertifying? could she be recertifying? could we be recertifying? could you be recertifying? could they be recertifying?
Perfect
could I have recertified? could you have recertified? could she have recertified? could we have recertified? could you have recertified? could they have recertified?
V-ing perfect
could I have been recertifying? could you have been recertifying? could she have been recertifying? could we have been recertifying? could you have been recertifying? could they have been recertifying?
Interro-negative form
Simple form
could I not recertify? could you not recertify? could she not recertify? could we not recertify? could you not recertify? could they not recertify?
V-ing form
could I not be recertifying? could you not be recertifying? could she not be recertifying? could we not be recertifying? could you not be recertifying? could they not be recertifying?
Perfect
could I not have recertified? could you not have recertified? could she not have recertified? could we not have recertified? could you not have recertified? could they not have recertified?
V-ing perfect
could I not have been recertifying? could you not have been recertifying? could she not have been recertifying? could we not have been recertifying? could you not have been recertifying? could they not have been recertifying?