could skin
Regular verb: skin - skinned- skinned

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could skin
you could skin
she could skin
we could skin
you could skin
they could skin 	I could be skinning
you could be skinning
she could be skinning
we could be skinning
you could be skinning
they could be skinning	I could have skinned
you could have skinned
she could have skinned
we could have skinned
you could have skinned
they could have skinned	I could have been skinning
you could have been skinning
she could have been skinning
we could have been skinning
you could have been skinning
they could have been skinning	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not skin
you could not skin
she could not skin
we could not skin
you could not skin
they could not skin 	I could not be skinning
you could not be skinning
she could not be skinning
we could not be skinning
you could not be skinning
they could not be skinning	I could not have skinned
you could not have skinned
she could not have skinned
we could not have skinned
you could not have skinned
they could not have skinned	I could not have been skinning
you could not have been skinning
she could not have been skinning
we could not have been skinning
you could not have been skinning
they could not have been skinning	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I skin?
could you skin?
could she skin?
could we skin?
could you skin?
could they skin? 	could I be skinning?
could you be skinning?
could she be skinning?
could we be skinning?
could you be skinning?
could they be skinning? 	could I have skinned?
could you have skinned?
could she have skinned?
could we have skinned?
could you have skinned?
could they have skinned? 	could I have been skinning?
could you have been skinning?
could she have been skinning?
could we have been skinning?
could you have been skinning?
could they have been skinning? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not skin?
could you not skin?
could she not skin?
could we not skin?
could you not skin?
could they not skin? 	could I not be skinning?
could you not be skinning?
could she not be skinning?
could we not be skinning?
could you not be skinning?
could they not be skinning? 	could I not have skinned?
could you not have skinned?
could she not have skinned?
could we not have skinned?
could you not have skinned?
could they not have skinned? 	could I not have been skinning?
could you not have been skinning?
could she not have been skinning?
could we not have been skinning?
could you not have been skinning?
could they not have been skinning?