must foster
Regular verb: foster - fostered- fostered

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must foster
you must foster
she must foster
we must foster
you must foster
they must foster 	I must be fostering
you must be fostering
she must be fostering
we must be fostering
you must be fostering
they must be fostering	I must have fostered
you must have fostered
she must have fostered
we must have fostered
you must have fostered
they must have fostered	I must have been fostering
you must have been fostering
she must have been fostering
we must have been fostering
you must have been fostering
they must have been fostering	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't foster
you mustn't foster
she mustn't foster
we mustn't foster
you mustn't foster
they mustn't foster 	I mustn't be fostering
you mustn't be fostering
she mustn't be fostering
we mustn't be fostering
you mustn't be fostering
they mustn't be fostering	I mustn't have fostered
you mustn't have fostered
she mustn't have fostered
we mustn't have fostered
you mustn't have fostered
they mustn't have fostered	I mustn't have been fostering
you mustn't have been fostering
she mustn't have been fostering
we mustn't have been fostering
you mustn't have been fostering
they mustn't have been fostering	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I foster?
must you foster?
must she foster?
must we foster?
must you foster?
must they foster? 	must I be fostering?
must you be fostering?
must she be fostering?
must we be fostering?
must you be fostering?
must they be fostering? 	must I have fostered?
must you have fostered?
must she have fostered?
must we have fostered?
must you have fostered?
must they have fostered? 	must I have been fostering?
must you have been fostering?
must she have been fostering?
must we have been fostering?
must you have been fostering?
must they have been fostering? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I foster?
mustn't you foster?
mustn't she foster?
mustn't we foster?
mustn't you foster?
mustn't they foster? 	mustn't I be fostering?
mustn't you be fostering?
mustn't she be fostering?
mustn't we be fostering?
mustn't you be fostering?
mustn't they be fostering? 	mustn't I have fostered?
mustn't you have fostered?
mustn't she have fostered?
mustn't we have fostered?
mustn't you have fostered?
mustn't they have fostered? 	mustn't I have been fostering?
mustn't you have been fostering?
mustn't she have been fostering?
mustn't we have been fostering?
mustn't you have been fostering?
mustn't they have been fostering?