English verb conjugation MUST OBSERVE

Regular verb: observe - observed - observed

Affirmation

Simple form

I must observe
you must observe
she must observe
we must observe
you must observe
they must observe

V-ing form

I must be observing
you must be observing
she must be observing
we must be observing
you must be observing
they must be observing

Perfect

I must have observed
you must have observed
she must have observed
we must have observed
you must have observed
they must have observed

V-ing perfect

I must have been observing
you must have been observing
she must have been observing
we must have been observing
you must have been observing
they must have been observing

Negation

Simple form

I mustn't observe
you mustn't observe
she mustn't observe
we mustn't observe
you mustn't observe
they mustn't observe

V-ing form

I mustn't be observing
you mustn't be observing
she mustn't be observing
we mustn't be observing
you mustn't be observing
they mustn't be observing

Perfect

I mustn't have observed
you mustn't have observed
she mustn't have observed
we mustn't have observed
you mustn't have observed
they mustn't have observed

V-ing perfect

I mustn't have been observing
you mustn't have been observing
she mustn't have been observing
we mustn't have been observing
you mustn't have been observing
they mustn't have been observing

Interrogative form

Simple form

must I observe?
must you observe?
must she observe?
must we observe?
must you observe?
must they observe?

V-ing form

must I be observing?
must you be observing?
must she be observing?
must we be observing?
must you be observing?
must they be observing?

Perfect

must I have observed?
must you have observed?
must she have observed?
must we have observed?
must you have observed?
must they have observed?

V-ing perfect

must I have been observing?
must you have been observing?
must she have been observing?
must we have been observing?
must you have been observing?
must they have been observing?

Interro-negative form

Simple form

mustn't I observe?
mustn't you observe?
mustn't she observe?
mustn't we observe?
mustn't you observe?
mustn't they observe?

V-ing form

mustn't I be observing?
mustn't you be observing?
mustn't she be observing?
mustn't we be observing?
mustn't you be observing?
mustn't they be observing?

Perfect

mustn't I have observed?
mustn't you have observed?
mustn't she have observed?
mustn't we have observed?
mustn't you have observed?
mustn't they have observed?

V-ing perfect

mustn't I have been observing?
mustn't you have been observing?
mustn't she have been observing?
mustn't we have been observing?
mustn't you have been observing?
mustn't they have been observing?

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