could gray
Regular verb: gray - grayed- grayed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could gray
you could gray
she could gray
we could gray
you could gray
they could gray 	I could be graying
you could be graying
she could be graying
we could be graying
you could be graying
they could be graying	I could have grayed
you could have grayed
she could have grayed
we could have grayed
you could have grayed
they could have grayed	I could have been graying
you could have been graying
she could have been graying
we could have been graying
you could have been graying
they could have been graying	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't gray
you couldn't gray
she couldn't gray
we couldn't gray
you couldn't gray
they couldn't gray 	I couldn't be graying
you couldn't be graying
she couldn't be graying
we couldn't be graying
you couldn't be graying
they couldn't be graying	I couldn't have grayed
you couldn't have grayed
she couldn't have grayed
we couldn't have grayed
you couldn't have grayed
they couldn't have grayed	I couldn't have been graying
you couldn't have been graying
she couldn't have been graying
we couldn't have been graying
you couldn't have been graying
they couldn't have been graying	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I gray?
could you gray?
could she gray?
could we gray?
could you gray?
could they gray? 	could I be graying?
could you be graying?
could she be graying?
could we be graying?
could you be graying?
could they be graying? 	could I have grayed?
could you have grayed?
could she have grayed?
could we have grayed?
could you have grayed?
could they have grayed? 	could I have been graying?
could you have been graying?
could she have been graying?
could we have been graying?
could you have been graying?
could they have been graying? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I gray?
couldn't you gray?
couldn't she gray?
couldn't we gray?
couldn't you gray?
couldn't they gray? 	couldn't I be graying?
couldn't you be graying?
couldn't she be graying?
couldn't we be graying?
couldn't you be graying?
couldn't they be graying? 	couldn't I have grayed?
couldn't you have grayed?
couldn't she have grayed?
couldn't we have grayed?
couldn't you have grayed?
couldn't they have grayed? 	couldn't I have been graying?
couldn't you have been graying?
couldn't she have been graying?
couldn't we have been graying?
couldn't you have been graying?
couldn't they have been graying?