must inquire
Regular verb: inquire - inquired- inquired

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must inquire
you must inquire
she must inquire
we must inquire
you must inquire
they must inquire 	I must be inquiring
you must be inquiring
she must be inquiring
we must be inquiring
you must be inquiring
they must be inquiring	I must have inquired
you must have inquired
she must have inquired
we must have inquired
you must have inquired
they must have inquired	I must have been inquiring
you must have been inquiring
she must have been inquiring
we must have been inquiring
you must have been inquiring
they must have been inquiring	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't inquire
you mustn't inquire
she mustn't inquire
we mustn't inquire
you mustn't inquire
they mustn't inquire 	I mustn't be inquiring
you mustn't be inquiring
she mustn't be inquiring
we mustn't be inquiring
you mustn't be inquiring
they mustn't be inquiring	I mustn't have inquired
you mustn't have inquired
she mustn't have inquired
we mustn't have inquired
you mustn't have inquired
they mustn't have inquired	I mustn't have been inquiring
you mustn't have been inquiring
she mustn't have been inquiring
we mustn't have been inquiring
you mustn't have been inquiring
they mustn't have been inquiring	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I inquire?
must you inquire?
must she inquire?
must we inquire?
must you inquire?
must they inquire? 	must I be inquiring?
must you be inquiring?
must she be inquiring?
must we be inquiring?
must you be inquiring?
must they be inquiring? 	must I have inquired?
must you have inquired?
must she have inquired?
must we have inquired?
must you have inquired?
must they have inquired? 	must I have been inquiring?
must you have been inquiring?
must she have been inquiring?
must we have been inquiring?
must you have been inquiring?
must they have been inquiring? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I inquire?
mustn't you inquire?
mustn't she inquire?
mustn't we inquire?
mustn't you inquire?
mustn't they inquire? 	mustn't I be inquiring?
mustn't you be inquiring?
mustn't she be inquiring?
mustn't we be inquiring?
mustn't you be inquiring?
mustn't they be inquiring? 	mustn't I have inquired?
mustn't you have inquired?
mustn't she have inquired?
mustn't we have inquired?
mustn't you have inquired?
mustn't they have inquired? 	mustn't I have been inquiring?
mustn't you have been inquiring?
mustn't she have been inquiring?
mustn't we have been inquiring?
mustn't you have been inquiring?
mustn't they have been inquiring?