should nibble
Regular verb: nibble - nibbled- nibbled

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I should nibble
you should nibble
she should nibble
we should nibble
you should nibble
they should nibble 	I should be nibbling
you should be nibbling
she should be nibbling
we should be nibbling
you should be nibbling
they should be nibbling	I should have nibbled
you should have nibbled
she should have nibbled
we should have nibbled
you should have nibbled
they should have nibbled	I should have been nibbling
you should have been nibbling
she should have been nibbling
we should have been nibbling
you should have been nibbling
they should have been nibbling	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I should not nibble
you should not nibble
she should not nibble
we should not nibble
you should not nibble
they should not nibble 	I should not be nibbling
you should not be nibbling
she should not be nibbling
we should not be nibbling
you should not be nibbling
they should not be nibbling	I should not have nibbled
you should not have nibbled
she should not have nibbled
we should not have nibbled
you should not have nibbled
they should not have nibbled	I should not have been nibbling
you should not have been nibbling
she should not have been nibbling
we should not have been nibbling
you should not have been nibbling
they should not have been nibbling	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
should I nibble?
should you nibble?
should she nibble?
should we nibble?
should you nibble?
should they nibble? 	should I be nibbling?
should you be nibbling?
should she be nibbling?
should we be nibbling?
should you be nibbling?
should they be nibbling? 	should I have nibbled?
should you have nibbled?
should she have nibbled?
should we have nibbled?
should you have nibbled?
should they have nibbled? 	should I have been nibbling?
should you have been nibbling?
should she have been nibbling?
should we have been nibbling?
should you have been nibbling?
should they have been nibbling? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
should I not nibble?
should you not nibble?
should she not nibble?
should we not nibble?
should you not nibble?
should they not nibble? 	should I not be nibbling?
should you not be nibbling?
should she not be nibbling?
should we not be nibbling?
should you not be nibbling?
should they not be nibbling? 	should I not have nibbled?
should you not have nibbled?
should she not have nibbled?
should we not have nibbled?
should you not have nibbled?
should they not have nibbled? 	should I not have been nibbling?
should you not have been nibbling?
should she not have been nibbling?
should we not have been nibbling?
should you not have been nibbling?
should they not have been nibbling?