could regrind
Irregular verb: regrind - reground- reground

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could regrind
you could regrind
she could regrind
we could regrind
you could regrind
they could regrind 	I could be regrinding
you could be regrinding
she could be regrinding
we could be regrinding
you could be regrinding
they could be regrinding	I could have reground
you could have reground
she could have reground
we could have reground
you could have reground
they could have reground	I could have been regrinding
you could have been regrinding
she could have been regrinding
we could have been regrinding
you could have been regrinding
they could have been regrinding	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't regrind
you couldn't regrind
she couldn't regrind
we couldn't regrind
you couldn't regrind
they couldn't regrind 	I couldn't be regrinding
you couldn't be regrinding
she couldn't be regrinding
we couldn't be regrinding
you couldn't be regrinding
they couldn't be regrinding	I couldn't have reground
you couldn't have reground
she couldn't have reground
we couldn't have reground
you couldn't have reground
they couldn't have reground	I couldn't have been regrinding
you couldn't have been regrinding
she couldn't have been regrinding
we couldn't have been regrinding
you couldn't have been regrinding
they couldn't have been regrinding	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I regrind?
could you regrind?
could she regrind?
could we regrind?
could you regrind?
could they regrind? 	could I be regrinding?
could you be regrinding?
could she be regrinding?
could we be regrinding?
could you be regrinding?
could they be regrinding? 	could I have reground?
could you have reground?
could she have reground?
could we have reground?
could you have reground?
could they have reground? 	could I have been regrinding?
could you have been regrinding?
could she have been regrinding?
could we have been regrinding?
could you have been regrinding?
could they have been regrinding? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I regrind?
couldn't you regrind?
couldn't she regrind?
couldn't we regrind?
couldn't you regrind?
couldn't they regrind? 	couldn't I be regrinding?
couldn't you be regrinding?
couldn't she be regrinding?
couldn't we be regrinding?
couldn't you be regrinding?
couldn't they be regrinding? 	couldn't I have reground?
couldn't you have reground?
couldn't she have reground?
couldn't we have reground?
couldn't you have reground?
couldn't they have reground? 	couldn't I have been regrinding?
couldn't you have been regrinding?
couldn't she have been regrinding?
couldn't we have been regrinding?
couldn't you have been regrinding?
couldn't they have been regrinding?