must abbreviate
Regular verb: abbreviate - abbreviated- abbreviated

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must abbreviate
you must abbreviate
she must abbreviate
we must abbreviate
you must abbreviate
they must abbreviate 	I must be abbreviating
you must be abbreviating
she must be abbreviating
we must be abbreviating
you must be abbreviating
they must be abbreviating	I must have abbreviated
you must have abbreviated
she must have abbreviated
we must have abbreviated
you must have abbreviated
they must have abbreviated	I must have been abbreviating
you must have been abbreviating
she must have been abbreviating
we must have been abbreviating
you must have been abbreviating
they must have been abbreviating	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must not abbreviate
you must not abbreviate
she must not abbreviate
we must not abbreviate
you must not abbreviate
they must not abbreviate 	I must not be abbreviating
you must not be abbreviating
she must not be abbreviating
we must not be abbreviating
you must not be abbreviating
they must not be abbreviating	I must not have abbreviated
you must not have abbreviated
she must not have abbreviated
we must not have abbreviated
you must not have abbreviated
they must not have abbreviated	I must not have been abbreviating
you must not have been abbreviating
she must not have been abbreviating
we must not have been abbreviating
you must not have been abbreviating
they must not have been abbreviating	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I abbreviate?
must you abbreviate?
must she abbreviate?
must we abbreviate?
must you abbreviate?
must they abbreviate? 	must I be abbreviating?
must you be abbreviating?
must she be abbreviating?
must we be abbreviating?
must you be abbreviating?
must they be abbreviating? 	must I have abbreviated?
must you have abbreviated?
must she have abbreviated?
must we have abbreviated?
must you have abbreviated?
must they have abbreviated? 	must I have been abbreviating?
must you have been abbreviating?
must she have been abbreviating?
must we have been abbreviating?
must you have been abbreviating?
must they have been abbreviating? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I not abbreviate?
must you not abbreviate?
must she not abbreviate?
must we not abbreviate?
must you not abbreviate?
must they not abbreviate? 	must I not be abbreviating?
must you not be abbreviating?
must she not be abbreviating?
must we not be abbreviating?
must you not be abbreviating?
must they not be abbreviating? 	must I not have abbreviated?
must you not have abbreviated?
must she not have abbreviated?
must we not have abbreviated?
must you not have abbreviated?
must they not have abbreviated? 	must I not have been abbreviating?
must you not have been abbreviating?
must she not have been abbreviating?
must we not have been abbreviating?
must you not have been abbreviating?
must they not have been abbreviating?