English verb conjugation
MUST CONCENTER

Regular verb: concenter - concentered - concentered

Affirmation

Simple form	V-ing form
I must concenter you must concenter he must concenter we must concenter you must concenter they must concenter	I must be concentering you must be concentering he must be concentering we must be concentering you must be concentering they must be concentering
Perfect	V-ing perfect
I must have concentered you must have concentered he must have concentered we must have concentered you must have concentered they must have concentered	I must have been concentering you must have been concentering he must have been concentering we must have been concentering you must have been concentering they must have been concentering

Negation

Simple form	V-ing form
I mustn't concenter you mustn't concenter he mustn't concenter we mustn't concenter you mustn't concenter they mustn't concenter	I mustn't be concentering you mustn't be concentering he mustn't be concentering we mustn't be concentering you mustn't be concentering they mustn't be concentering
Perfect	V-ing perfect
I mustn't have concentered you mustn't have concentered he mustn't have concentered we mustn't have concentered you mustn't have concentered they mustn't have concentered	I mustn't have been concentering you mustn't have been concentering he mustn't have been concentering we mustn't have been concentering you mustn't have been concentering they mustn't have been concentering

Interrogative form

Simple form	V-ing form
must I concenter? must you concenter? must he concenter? must we concenter? must you concenter? must they concenter?	must I be concentering? must you be concentering? must he be concentering? must we be concentering? must you be concentering? must they be concentering?
Perfect	V-ing perfect
must I have concentered? must you have concentered? must he have concentered? must we have concentered? must you have concentered? must they have concentered?	must I have been concentering? must you have been concentering? must he have been concentering? must we have been concentering? must you have been concentering? must they have been concentering?

Interro-negative form

Simple form	V-ing form
mustn't I concenter? mustn't you concenter? mustn't he concenter? mustn't we concenter? mustn't you concenter? mustn't they concenter?	mustn't I be concentering? mustn't you be concentering? mustn't he be concentering? mustn't we be concentering? mustn't you be concentering? mustn't they be concentering?
Perfect	V-ing perfect
mustn't I have concentered? mustn't you have concentered? mustn't he have concentered? mustn't we have concentered? mustn't you have concentered? mustn't they have concentered?	mustn't I have been concentering? mustn't you have been concentering? mustn't he have been concentering? mustn't we have been concentering? mustn't you have been concentering? mustn't they have been concentering?