must lack
Verbo regolare: lack - lacked- lacked

Affermazione 	
Forma semplice 	Forma con V-ing 	Perfetto 	Perfetto con V-ing 	
I must lack
you must lack
she must lack
we must lack
you must lack
they must lack 	I must be lacking
you must be lacking
she must be lacking
we must be lacking
you must be lacking
they must be lacking	I must have lacked
you must have lacked
she must have lacked
we must have lacked
you must have lacked
they must have lacked	I must have been lacking
you must have been lacking
she must have been lacking
we must have been lacking
you must have been lacking
they must have been lacking	

Negazione 	
Forma semplice 	Forma con V-ing 	Perfetto 	Perfetto con V-ing 	
I must not lack
you must not lack
she must not lack
we must not lack
you must not lack
they must not lack 	I must not be lacking
you must not be lacking
she must not be lacking
we must not be lacking
you must not be lacking
they must not be lacking	I must not have lacked
you must not have lacked
she must not have lacked
we must not have lacked
you must not have lacked
they must not have lacked	I must not have been lacking
you must not have been lacking
she must not have been lacking
we must not have been lacking
you must not have been lacking
they must not have been lacking	

Forma interrogativa 	
Forma semplice 	Forma con V-ing 	Perfetto 	Perfetto con V-ing 	
must I lack?
must you lack?
must she lack?
must we lack?
must you lack?
must they lack? 	must I be lacking?
must you be lacking?
must she be lacking?
must we be lacking?
must you be lacking?
must they be lacking? 	must I have lacked?
must you have lacked?
must she have lacked?
must we have lacked?
must you have lacked?
must they have lacked? 	must I have been lacking?
must you have been lacking?
must she have been lacking?
must we have been lacking?
must you have been lacking?
must they have been lacking? 	

Forma interro-negativa 	
Forma semplice 	Forma con V-ing 	Perfetto 	Perfetto con V-ing 	
must I not lack?
must you not lack?
must she not lack?
must we not lack?
must you not lack?
must they not lack? 	must I not be lacking?
must you not be lacking?
must she not be lacking?
must we not be lacking?
must you not be lacking?
must they not be lacking? 	must I not have lacked?
must you not have lacked?
must she not have lacked?
must we not have lacked?
must you not have lacked?
must they not have lacked? 	must I not have been lacking?
must you not have been lacking?
must she not have been lacking?
must we not have been lacking?
must you not have been lacking?
must they not have been lacking?