female gender | Modal : no | may | might | can | could | shall | should | will | would | must | ought to
English verb conjugation MUST LACK
Regular verb: lack - lacked - lacked
Affirmation
Simple form
I must lackyou must lack
he must lack
we must lack
you must lack
they must lack
V-ing form
I must be lackingyou must be lacking
he must be lacking
we must be lacking
you must be lacking
they must be lacking
Perfect
I must have lackedyou must have lacked
he must have lacked
we must have lacked
you must have lacked
they must have lacked
V-ing perfect
I must have been lackingyou must have been lacking
he must have been lacking
we must have been lacking
you must have been lacking
they must have been lacking
Negation
Simple form
I mustn't lackyou mustn't lack
he mustn't lack
we mustn't lack
you mustn't lack
they mustn't lack
V-ing form
I mustn't be lackingyou mustn't be lacking
he mustn't be lacking
we mustn't be lacking
you mustn't be lacking
they mustn't be lacking
Perfect
I mustn't have lackedyou mustn't have lacked
he mustn't have lacked
we mustn't have lacked
you mustn't have lacked
they mustn't have lacked
V-ing perfect
I mustn't have been lackingyou mustn't have been lacking
he mustn't have been lacking
we mustn't have been lacking
you mustn't have been lacking
they mustn't have been lacking
Interrogative form
Simple form
must I lack?must you lack?
must he lack?
must we lack?
must you lack?
must they lack?
V-ing form
must I be lacking?must you be lacking?
must he be lacking?
must we be lacking?
must you be lacking?
must they be lacking?
Perfect
must I have lacked?must you have lacked?
must he have lacked?
must we have lacked?
must you have lacked?
must they have lacked?
V-ing perfect
must I have been lacking?must you have been lacking?
must he have been lacking?
must we have been lacking?
must you have been lacking?
must they have been lacking?
Interro-negative form
Simple form
mustn't I lack?mustn't you lack?
mustn't he lack?
mustn't we lack?
mustn't you lack?
mustn't they lack?
V-ing form
mustn't I be lacking?mustn't you be lacking?
mustn't he be lacking?
mustn't we be lacking?
mustn't you be lacking?
mustn't they be lacking?
Perfect
mustn't I have lacked?mustn't you have lacked?
mustn't he have lacked?
mustn't we have lacked?
mustn't you have lacked?
mustn't they have lacked?
V-ing perfect
mustn't I have been lacking?mustn't you have been lacking?
mustn't he have been lacking?
mustn't we have been lacking?
mustn't you have been lacking?
mustn't they have been lacking?