I must strain you must strain she must strain we must strain you must strain they must strain
Forma con V-ing
I must be straining you must be straining she must be straining we must be straining you must be straining they must be straining
Perfecto
I must have strained you must have strained she must have strained we must have strained you must have strained they must have strained
Perfecto con V-ing
I must have been straining you must have been straining she must have been straining we must have been straining you must have been straining they must have been straining
Negación
Forma simple
I must not strain you must not strain she must not strain we must not strain you must not strain they must not strain
Forma con V-ing
I must not be straining you must not be straining she must not be straining we must not be straining you must not be straining they must not be straining
Perfecto
I must not have strained you must not have strained she must not have strained we must not have strained you must not have strained they must not have strained
Perfecto con V-ing
I must not have been straining you must not have been straining she must not have been straining we must not have been straining you must not have been straining they must not have been straining
Forma interrogativa
Forma simple
must I strain? must you strain? must she strain? must we strain? must you strain? must they strain?
Forma con V-ing
must I be straining? must you be straining? must she be straining? must we be straining? must you be straining? must they be straining?
Perfecto
must I have strained? must you have strained? must she have strained? must we have strained? must you have strained? must they have strained?
Perfecto con V-ing
must I have been straining? must you have been straining? must she have been straining? must we have been straining? must you have been straining? must they have been straining?
Forma interro-negativa
Forma simple
must I not strain? must you not strain? must she not strain? must we not strain? must you not strain? must they not strain?
Forma con V-ing
must I not be straining? must you not be straining? must she not be straining? must we not be straining? must you not be straining? must they not be straining?
Perfecto
must I not have strained? must you not have strained? must she not have strained? must we not have strained? must you not have strained? must they not have strained?
Perfecto con V-ing
must I not have been straining? must you not have been straining? must she not have been straining? must we not have been straining? must you not have been straining? must they not have been straining?