I must write you must write she must write we must write you must write they must write
Forma con V-ing
I must be writing you must be writing she must be writing we must be writing you must be writing they must be writing
Perfecto
I must have written you must have written she must have written we must have written you must have written they must have written
Perfecto con V-ing
I must have been writing you must have been writing she must have been writing we must have been writing you must have been writing they must have been writing
Negación
Forma simple
I mustn't write you mustn't write she mustn't write we mustn't write you mustn't write they mustn't write
Forma con V-ing
I mustn't be writing you mustn't be writing she mustn't be writing we mustn't be writing you mustn't be writing they mustn't be writing
Perfecto
I mustn't have written you mustn't have written she mustn't have written we mustn't have written you mustn't have written they mustn't have written
Perfecto con V-ing
I mustn't have been writing you mustn't have been writing she mustn't have been writing we mustn't have been writing you mustn't have been writing they mustn't have been writing
Forma interrogativa
Forma simple
must I write? must you write? must she write? must we write? must you write? must they write?
Forma con V-ing
must I be writing? must you be writing? must she be writing? must we be writing? must you be writing? must they be writing?
Perfecto
must I have written? must you have written? must she have written? must we have written? must you have written? must they have written?
Perfecto con V-ing
must I have been writing? must you have been writing? must she have been writing? must we have been writing? must you have been writing? must they have been writing?
Forma interro-negativa
Forma simple
mustn't I write? mustn't you write? mustn't she write? mustn't we write? mustn't you write? mustn't they write?
Forma con V-ing
mustn't I be writing? mustn't you be writing? mustn't she be writing? mustn't we be writing? mustn't you be writing? mustn't they be writing?
Perfecto
mustn't I have written? mustn't you have written? mustn't she have written? mustn't we have written? mustn't you have written? mustn't they have written?
Perfecto con V-ing
mustn't I have been writing? mustn't you have been writing? mustn't she have been writing? mustn't we have been writing? mustn't you have been writing? mustn't they have been writing?