English verb conjugation MUST SIEVE

Regular verb: sieve - sieved - sieved

Affirmation

Simple form

I must sieve
you must sieve
he must sieve
we must sieve
you must sieve
they must sieve

V-ing form

I must be sieving
you must be sieving
he must be sieving
we must be sieving
you must be sieving
they must be sieving

Perfect

I must have sieved
you must have sieved
he must have sieved
we must have sieved
you must have sieved
they must have sieved

V-ing perfect

I must have been sieving
you must have been sieving
he must have been sieving
we must have been sieving
you must have been sieving
they must have been sieving

Negation

Simple form

I mustn't sieve
you mustn't sieve
he mustn't sieve
we mustn't sieve
you mustn't sieve
they mustn't sieve

V-ing form

I mustn't be sieving
you mustn't be sieving
he mustn't be sieving
we mustn't be sieving
you mustn't be sieving
they mustn't be sieving

Perfect

I mustn't have sieved
you mustn't have sieved
he mustn't have sieved
we mustn't have sieved
you mustn't have sieved
they mustn't have sieved

V-ing perfect

I mustn't have been sieving
you mustn't have been sieving
he mustn't have been sieving
we mustn't have been sieving
you mustn't have been sieving
they mustn't have been sieving

Interrogative form

Simple form

must I sieve?
must you sieve?
must he sieve?
must we sieve?
must you sieve?
must they sieve?

V-ing form

must I be sieving?
must you be sieving?
must he be sieving?
must we be sieving?
must you be sieving?
must they be sieving?

Perfect

must I have sieved?
must you have sieved?
must he have sieved?
must we have sieved?
must you have sieved?
must they have sieved?

V-ing perfect

must I have been sieving?
must you have been sieving?
must he have been sieving?
must we have been sieving?
must you have been sieving?
must they have been sieving?

Interro-negative form

Simple form

mustn't I sieve?
mustn't you sieve?
mustn't he sieve?
mustn't we sieve?
mustn't you sieve?
mustn't they sieve?

V-ing form

mustn't I be sieving?
mustn't you be sieving?
mustn't he be sieving?
mustn't we be sieving?
mustn't you be sieving?
mustn't they be sieving?

Perfect

mustn't I have sieved?
mustn't you have sieved?
mustn't he have sieved?
mustn't we have sieved?
mustn't you have sieved?
mustn't they have sieved?

V-ing perfect

mustn't I have been sieving?
mustn't you have been sieving?
mustn't he have been sieving?
mustn't we have been sieving?
mustn't you have been sieving?
mustn't they have been sieving?

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