could case
Regular verb: case - cased- cased

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could case
you could case
she could case
we could case
you could case
they could case 	I could be casing
you could be casing
she could be casing
we could be casing
you could be casing
they could be casing	I could have cased
you could have cased
she could have cased
we could have cased
you could have cased
they could have cased	I could have been casing
you could have been casing
she could have been casing
we could have been casing
you could have been casing
they could have been casing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't case
you couldn't case
she couldn't case
we couldn't case
you couldn't case
they couldn't case 	I couldn't be casing
you couldn't be casing
she couldn't be casing
we couldn't be casing
you couldn't be casing
they couldn't be casing	I couldn't have cased
you couldn't have cased
she couldn't have cased
we couldn't have cased
you couldn't have cased
they couldn't have cased	I couldn't have been casing
you couldn't have been casing
she couldn't have been casing
we couldn't have been casing
you couldn't have been casing
they couldn't have been casing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I case?
could you case?
could she case?
could we case?
could you case?
could they case? 	could I be casing?
could you be casing?
could she be casing?
could we be casing?
could you be casing?
could they be casing? 	could I have cased?
could you have cased?
could she have cased?
could we have cased?
could you have cased?
could they have cased? 	could I have been casing?
could you have been casing?
could she have been casing?
could we have been casing?
could you have been casing?
could they have been casing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I case?
couldn't you case?
couldn't she case?
couldn't we case?
couldn't you case?
couldn't they case? 	couldn't I be casing?
couldn't you be casing?
couldn't she be casing?
couldn't we be casing?
couldn't you be casing?
couldn't they be casing? 	couldn't I have cased?
couldn't you have cased?
couldn't she have cased?
couldn't we have cased?
couldn't you have cased?
couldn't they have cased? 	couldn't I have been casing?
couldn't you have been casing?
couldn't she have been casing?
couldn't we have been casing?
couldn't you have been casing?
couldn't they have been casing?