must house-train
Regular verb: house-train - house-trained- house-trained

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must house-train
you must house-train
he must house-train
we must house-train
you must house-train
they must house-train 	I must be house-training
you must be house-training
he must be house-training
we must be house-training
you must be house-training
they must be house-training	I must have house-trained
you must have house-trained
he must have house-trained
we must have house-trained
you must have house-trained
they must have house-trained	I must have been house-training
you must have been house-training
he must have been house-training
we must have been house-training
you must have been house-training
they must have been house-training	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must not house-train
you must not house-train
he must not house-train
we must not house-train
you must not house-train
they must not house-train 	I must not be house-training
you must not be house-training
he must not be house-training
we must not be house-training
you must not be house-training
they must not be house-training	I must not have house-trained
you must not have house-trained
he must not have house-trained
we must not have house-trained
you must not have house-trained
they must not have house-trained	I must not have been house-training
you must not have been house-training
he must not have been house-training
we must not have been house-training
you must not have been house-training
they must not have been house-training	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I house-train?
must you house-train?
must he house-train?
must we house-train?
must you house-train?
must they house-train? 	must I be house-training?
must you be house-training?
must he be house-training?
must we be house-training?
must you be house-training?
must they be house-training? 	must I have house-trained?
must you have house-trained?
must he have house-trained?
must we have house-trained?
must you have house-trained?
must they have house-trained? 	must I have been house-training?
must you have been house-training?
must he have been house-training?
must we have been house-training?
must you have been house-training?
must they have been house-training? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I not house-train?
must you not house-train?
must he not house-train?
must we not house-train?
must you not house-train?
must they not house-train? 	must I not be house-training?
must you not be house-training?
must he not be house-training?
must we not be house-training?
must you not be house-training?
must they not be house-training? 	must I not have house-trained?
must you not have house-trained?
must he not have house-trained?
must we not have house-trained?
must you not have house-trained?
must they not have house-trained? 	must I not have been house-training?
must you not have been house-training?
must he not have been house-training?
must we not have been house-training?
must you not have been house-training?
must they not have been house-training?