could concertise
Regular verb: concertise - concertised- concertised

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could concertise
you could concertise
he could concertise
we could concertise
you could concertise
they could concertise 	I could be concertising
you could be concertising
he could be concertising
we could be concertising
you could be concertising
they could be concertising	I could have concertised
you could have concertised
he could have concertised
we could have concertised
you could have concertised
they could have concertised	I could have been concertising
you could have been concertising
he could have been concertising
we could have been concertising
you could have been concertising
they could have been concertising	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not concertise
you could not concertise
he could not concertise
we could not concertise
you could not concertise
they could not concertise 	I could not be concertising
you could not be concertising
he could not be concertising
we could not be concertising
you could not be concertising
they could not be concertising	I could not have concertised
you could not have concertised
he could not have concertised
we could not have concertised
you could not have concertised
they could not have concertised	I could not have been concertising
you could not have been concertising
he could not have been concertising
we could not have been concertising
you could not have been concertising
they could not have been concertising	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I concertise?
could you concertise?
could he concertise?
could we concertise?
could you concertise?
could they concertise? 	could I be concertising?
could you be concertising?
could he be concertising?
could we be concertising?
could you be concertising?
could they be concertising? 	could I have concertised?
could you have concertised?
could he have concertised?
could we have concertised?
could you have concertised?
could they have concertised? 	could I have been concertising?
could you have been concertising?
could he have been concertising?
could we have been concertising?
could you have been concertising?
could they have been concertising? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not concertise?
could you not concertise?
could he not concertise?
could we not concertise?
could you not concertise?
could they not concertise? 	could I not be concertising?
could you not be concertising?
could he not be concertising?
could we not be concertising?
could you not be concertising?
could they not be concertising? 	could I not have concertised?
could you not have concertised?
could he not have concertised?
could we not have concertised?
could you not have concertised?
could they not have concertised? 	could I not have been concertising?
could you not have been concertising?
could he not have been concertising?
could we not have been concertising?
could you not have been concertising?
could they not have been concertising?