must underprop
Verbe régulier : underprop - underproped- underproped

Affirmation 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
I must underprop
you must underprop
she must underprop
we must underprop
you must underprop
they must underprop 	I must be underproping
you must be underproping
she must be underproping
we must be underproping
you must be underproping
they must be underproping	I must have underproped
you must have underproped
she must have underproped
we must have underproped
you must have underproped
they must have underproped	I must have been underproping
you must have been underproping
she must have been underproping
we must have been underproping
you must have been underproping
they must have been underproping	

Négation 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
I must not underprop
you must not underprop
she must not underprop
we must not underprop
you must not underprop
they must not underprop 	I must not be underproping
you must not be underproping
she must not be underproping
we must not be underproping
you must not be underproping
they must not be underproping	I must not have underproped
you must not have underproped
she must not have underproped
we must not have underproped
you must not have underproped
they must not have underproped	I must not have been underproping
you must not have been underproping
she must not have been underproping
we must not have been underproping
you must not have been underproping
they must not have been underproping	

Forme interrogative 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
must I underprop?
must you underprop?
must she underprop?
must we underprop?
must you underprop?
must they underprop? 	must I be underproping?
must you be underproping?
must she be underproping?
must we be underproping?
must you be underproping?
must they be underproping? 	must I have underproped?
must you have underproped?
must she have underproped?
must we have underproped?
must you have underproped?
must they have underproped? 	must I have been underproping?
must you have been underproping?
must she have been underproping?
must we have been underproping?
must you have been underproping?
must they have been underproping? 	

Forme interro-négative 	
Forme simple 	Forme en V-ing 	Perfect 	Perfect en V-ing 	
must I not underprop?
must you not underprop?
must she not underprop?
must we not underprop?
must you not underprop?
must they not underprop? 	must I not be underproping?
must you not be underproping?
must she not be underproping?
must we not be underproping?
must you not be underproping?
must they not be underproping? 	must I not have underproped?
must you not have underproped?
must she not have underproped?
must we not have underproped?
must you not have underproped?
must they not have underproped? 	must I not have been underproping?
must you not have been underproping?
must she not have been underproping?
must we not have been underproping?
must you not have been underproping?
must they not have been underproping?