could rot
Regular verb: rot - rotted- rotted

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could rot
you could rot
he could rot
we could rot
you could rot
they could rot 	I could be rotting
you could be rotting
he could be rotting
we could be rotting
you could be rotting
they could be rotting	I could have rotted
you could have rotted
he could have rotted
we could have rotted
you could have rotted
they could have rotted	I could have been rotting
you could have been rotting
he could have been rotting
we could have been rotting
you could have been rotting
they could have been rotting	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't rot
you couldn't rot
he couldn't rot
we couldn't rot
you couldn't rot
they couldn't rot 	I couldn't be rotting
you couldn't be rotting
he couldn't be rotting
we couldn't be rotting
you couldn't be rotting
they couldn't be rotting	I couldn't have rotted
you couldn't have rotted
he couldn't have rotted
we couldn't have rotted
you couldn't have rotted
they couldn't have rotted	I couldn't have been rotting
you couldn't have been rotting
he couldn't have been rotting
we couldn't have been rotting
you couldn't have been rotting
they couldn't have been rotting	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I rot?
could you rot?
could he rot?
could we rot?
could you rot?
could they rot? 	could I be rotting?
could you be rotting?
could he be rotting?
could we be rotting?
could you be rotting?
could they be rotting? 	could I have rotted?
could you have rotted?
could he have rotted?
could we have rotted?
could you have rotted?
could they have rotted? 	could I have been rotting?
could you have been rotting?
could he have been rotting?
could we have been rotting?
could you have been rotting?
could they have been rotting? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I rot?
couldn't you rot?
couldn't he rot?
couldn't we rot?
couldn't you rot?
couldn't they rot? 	couldn't I be rotting?
couldn't you be rotting?
couldn't he be rotting?
couldn't we be rotting?
couldn't you be rotting?
couldn't they be rotting? 	couldn't I have rotted?
couldn't you have rotted?
couldn't he have rotted?
couldn't we have rotted?
couldn't you have rotted?
couldn't they have rotted? 	couldn't I have been rotting?
couldn't you have been rotting?
couldn't he have been rotting?
couldn't we have been rotting?
couldn't you have been rotting?
couldn't they have been rotting?