must piggyback
Verbo regular: piggyback - piggybacked- piggybacked

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must piggyback
you must piggyback
he must piggyback
we must piggyback
you must piggyback
they must piggyback 	I must be piggybacking
you must be piggybacking
he must be piggybacking
we must be piggybacking
you must be piggybacking
they must be piggybacking	I must have piggybacked
you must have piggybacked
he must have piggybacked
we must have piggybacked
you must have piggybacked
they must have piggybacked	I must have been piggybacking
you must have been piggybacking
he must have been piggybacking
we must have been piggybacking
you must have been piggybacking
they must have been piggybacking	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must not piggyback
you must not piggyback
he must not piggyback
we must not piggyback
you must not piggyback
they must not piggyback 	I must not be piggybacking
you must not be piggybacking
he must not be piggybacking
we must not be piggybacking
you must not be piggybacking
they must not be piggybacking	I must not have piggybacked
you must not have piggybacked
he must not have piggybacked
we must not have piggybacked
you must not have piggybacked
they must not have piggybacked	I must not have been piggybacking
you must not have been piggybacking
he must not have been piggybacking
we must not have been piggybacking
you must not have been piggybacking
they must not have been piggybacking	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I piggyback?
must you piggyback?
must he piggyback?
must we piggyback?
must you piggyback?
must they piggyback? 	must I be piggybacking?
must you be piggybacking?
must he be piggybacking?
must we be piggybacking?
must you be piggybacking?
must they be piggybacking? 	must I have piggybacked?
must you have piggybacked?
must he have piggybacked?
must we have piggybacked?
must you have piggybacked?
must they have piggybacked? 	must I have been piggybacking?
must you have been piggybacking?
must he have been piggybacking?
must we have been piggybacking?
must you have been piggybacking?
must they have been piggybacking? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I not piggyback?
must you not piggyback?
must he not piggyback?
must we not piggyback?
must you not piggyback?
must they not piggyback? 	must I not be piggybacking?
must you not be piggybacking?
must he not be piggybacking?
must we not be piggybacking?
must you not be piggybacking?
must they not be piggybacking? 	must I not have piggybacked?
must you not have piggybacked?
must he not have piggybacked?
must we not have piggybacked?
must you not have piggybacked?
must they not have piggybacked? 	must I not have been piggybacking?
must you not have been piggybacking?
must he not have been piggybacking?
must we not have been piggybacking?
must you not have been piggybacking?
must they not have been piggybacking?