can concert
Regular verb: concert - concerted- concerted

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can concert
you can concert
he can concert
we can concert
you can concert
they can concert 	I can be concerting
you can be concerting
he can be concerting
we can be concerting
you can be concerting
they can be concerting	I can have concerted
you can have concerted
he can have concerted
we can have concerted
you can have concerted
they can have concerted	I can have been concerting
you can have been concerting
he can have been concerting
we can have been concerting
you can have been concerting
they can have been concerting	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can't concert
you can't concert
he can't concert
we can't concert
you can't concert
they can't concert 	I can't be concerting
you can't be concerting
he can't be concerting
we can't be concerting
you can't be concerting
they can't be concerting	I can't have concerted
you can't have concerted
he can't have concerted
we can't have concerted
you can't have concerted
they can't have concerted	I can't have been concerting
you can't have been concerting
he can't have been concerting
we can't have been concerting
you can't have been concerting
they can't have been concerting	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can I concert?
can you concert?
can he concert?
can we concert?
can you concert?
can they concert? 	can I be concerting?
can you be concerting?
can he be concerting?
can we be concerting?
can you be concerting?
can they be concerting? 	can I have concerted?
can you have concerted?
can he have concerted?
can we have concerted?
can you have concerted?
can they have concerted? 	can I have been concerting?
can you have been concerting?
can he have been concerting?
can we have been concerting?
can you have been concerting?
can they have been concerting? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can't I concert?
can't you concert?
can't he concert?
can't we concert?
can't you concert?
can't they concert? 	can't I be concerting?
can't you be concerting?
can't he be concerting?
can't we be concerting?
can't you be concerting?
can't they be concerting? 	can't I have concerted?
can't you have concerted?
can't he have concerted?
can't we have concerted?
can't you have concerted?
can't they have concerted? 	can't I have been concerting?
can't you have been concerting?
can't he have been concerting?
can't we have been concerting?
can't you have been concerting?
can't they have been concerting?