I must try you must try he must try we must try you must try they must try
Forma con V-ing
I must be trying you must be trying he must be trying we must be trying you must be trying they must be trying
Perfecto
I must have tried you must have tried he must have tried we must have tried you must have tried they must have tried
Perfecto con V-ing
I must have been trying you must have been trying he must have been trying we must have been trying you must have been trying they must have been trying
Negación
Forma simple
I must not try you must not try he must not try we must not try you must not try they must not try
Forma con V-ing
I must not be trying you must not be trying he must not be trying we must not be trying you must not be trying they must not be trying
Perfecto
I must not have tried you must not have tried he must not have tried we must not have tried you must not have tried they must not have tried
Perfecto con V-ing
I must not have been trying you must not have been trying he must not have been trying we must not have been trying you must not have been trying they must not have been trying
Forma interrogativa
Forma simple
must I try? must you try? must he try? must we try? must you try? must they try?
Forma con V-ing
must I be trying? must you be trying? must he be trying? must we be trying? must you be trying? must they be trying?
Perfecto
must I have tried? must you have tried? must he have tried? must we have tried? must you have tried? must they have tried?
Perfecto con V-ing
must I have been trying? must you have been trying? must he have been trying? must we have been trying? must you have been trying? must they have been trying?
Forma interro-negativa
Forma simple
must I not try? must you not try? must he not try? must we not try? must you not try? must they not try?
Forma con V-ing
must I not be trying? must you not be trying? must he not be trying? must we not be trying? must you not be trying? must they not be trying?
Perfecto
must I not have tried? must you not have tried? must he not have tried? must we not have tried? must you not have tried? must they not have tried?
Perfecto con V-ing
must I not have been trying? must you not have been trying? must he not have been trying? must we not have been trying? must you not have been trying? must they not have been trying?