should snowball
Regular verb: snowball - snowballed- snowballed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I should snowball
you should snowball
he should snowball
we should snowball
you should snowball
they should snowball 	I should be snowballing
you should be snowballing
he should be snowballing
we should be snowballing
you should be snowballing
they should be snowballing	I should have snowballed
you should have snowballed
he should have snowballed
we should have snowballed
you should have snowballed
they should have snowballed	I should have been snowballing
you should have been snowballing
he should have been snowballing
we should have been snowballing
you should have been snowballing
they should have been snowballing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I should not snowball
you should not snowball
he should not snowball
we should not snowball
you should not snowball
they should not snowball 	I should not be snowballing
you should not be snowballing
he should not be snowballing
we should not be snowballing
you should not be snowballing
they should not be snowballing	I should not have snowballed
you should not have snowballed
he should not have snowballed
we should not have snowballed
you should not have snowballed
they should not have snowballed	I should not have been snowballing
you should not have been snowballing
he should not have been snowballing
we should not have been snowballing
you should not have been snowballing
they should not have been snowballing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
should I snowball?
should you snowball?
should he snowball?
should we snowball?
should you snowball?
should they snowball? 	should I be snowballing?
should you be snowballing?
should he be snowballing?
should we be snowballing?
should you be snowballing?
should they be snowballing? 	should I have snowballed?
should you have snowballed?
should he have snowballed?
should we have snowballed?
should you have snowballed?
should they have snowballed? 	should I have been snowballing?
should you have been snowballing?
should he have been snowballing?
should we have been snowballing?
should you have been snowballing?
should they have been snowballing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
should I not snowball?
should you not snowball?
should he not snowball?
should we not snowball?
should you not snowball?
should they not snowball? 	should I not be snowballing?
should you not be snowballing?
should he not be snowballing?
should we not be snowballing?
should you not be snowballing?
should they not be snowballing? 	should I not have snowballed?
should you not have snowballed?
should he not have snowballed?
should we not have snowballed?
should you not have snowballed?
should they not have snowballed? 	should I not have been snowballing?
should you not have been snowballing?
should he not have been snowballing?
should we not have been snowballing?
should you not have been snowballing?
should they not have been snowballing?