must harness
Regular verb: harness - harnessed- harnessed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must harness
you must harness
he must harness
we must harness
you must harness
they must harness 	I must be harnessing
you must be harnessing
he must be harnessing
we must be harnessing
you must be harnessing
they must be harnessing	I must have harnessed
you must have harnessed
he must have harnessed
we must have harnessed
you must have harnessed
they must have harnessed	I must have been harnessing
you must have been harnessing
he must have been harnessing
we must have been harnessing
you must have been harnessing
they must have been harnessing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must not harness
you must not harness
he must not harness
we must not harness
you must not harness
they must not harness 	I must not be harnessing
you must not be harnessing
he must not be harnessing
we must not be harnessing
you must not be harnessing
they must not be harnessing	I must not have harnessed
you must not have harnessed
he must not have harnessed
we must not have harnessed
you must not have harnessed
they must not have harnessed	I must not have been harnessing
you must not have been harnessing
he must not have been harnessing
we must not have been harnessing
you must not have been harnessing
they must not have been harnessing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I harness?
must you harness?
must he harness?
must we harness?
must you harness?
must they harness? 	must I be harnessing?
must you be harnessing?
must he be harnessing?
must we be harnessing?
must you be harnessing?
must they be harnessing? 	must I have harnessed?
must you have harnessed?
must he have harnessed?
must we have harnessed?
must you have harnessed?
must they have harnessed? 	must I have been harnessing?
must you have been harnessing?
must he have been harnessing?
must we have been harnessing?
must you have been harnessing?
must they have been harnessing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I not harness?
must you not harness?
must he not harness?
must we not harness?
must you not harness?
must they not harness? 	must I not be harnessing?
must you not be harnessing?
must he not be harnessing?
must we not be harnessing?
must you not be harnessing?
must they not be harnessing? 	must I not have harnessed?
must you not have harnessed?
must he not have harnessed?
must we not have harnessed?
must you not have harnessed?
must they not have harnessed? 	must I not have been harnessing?
must you not have been harnessing?
must he not have been harnessing?
must we not have been harnessing?
must you not have been harnessing?
must they not have been harnessing?