male gender | Modal : no | may | might | can | could | shall | should | will | would | must | ought to
English verb conjugation MUST FAIL
Regular verb: fail - failed - failed
Affirmation
Simple form
I must failyou must fail
she must fail
we must fail
you must fail
they must fail
V-ing form
I must be failingyou must be failing
she must be failing
we must be failing
you must be failing
they must be failing
Perfect
I must have failedyou must have failed
she must have failed
we must have failed
you must have failed
they must have failed
V-ing perfect
I must have been failingyou must have been failing
she must have been failing
we must have been failing
you must have been failing
they must have been failing
Negation
Simple form
I mustn't failyou mustn't fail
she mustn't fail
we mustn't fail
you mustn't fail
they mustn't fail
V-ing form
I mustn't be failingyou mustn't be failing
she mustn't be failing
we mustn't be failing
you mustn't be failing
they mustn't be failing
Perfect
I mustn't have failedyou mustn't have failed
she mustn't have failed
we mustn't have failed
you mustn't have failed
they mustn't have failed
V-ing perfect
I mustn't have been failingyou mustn't have been failing
she mustn't have been failing
we mustn't have been failing
you mustn't have been failing
they mustn't have been failing
Interrogative form
Simple form
must I fail?must you fail?
must she fail?
must we fail?
must you fail?
must they fail?
V-ing form
must I be failing?must you be failing?
must she be failing?
must we be failing?
must you be failing?
must they be failing?
Perfect
must I have failed?must you have failed?
must she have failed?
must we have failed?
must you have failed?
must they have failed?
V-ing perfect
must I have been failing?must you have been failing?
must she have been failing?
must we have been failing?
must you have been failing?
must they have been failing?
Interro-negative form
Simple form
mustn't I fail?mustn't you fail?
mustn't she fail?
mustn't we fail?
mustn't you fail?
mustn't they fail?
V-ing form
mustn't I be failing?mustn't you be failing?
mustn't she be failing?
mustn't we be failing?
mustn't you be failing?
mustn't they be failing?
Perfect
mustn't I have failed?mustn't you have failed?
mustn't she have failed?
mustn't we have failed?
mustn't you have failed?
mustn't they have failed?
V-ing perfect
mustn't I have been failing?mustn't you have been failing?
mustn't she have been failing?
mustn't we have been failing?
mustn't you have been failing?
mustn't they have been failing?