could scumble
Regular verb: scumble - scumbled- scumbled

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could scumble
you could scumble
he could scumble
we could scumble
you could scumble
they could scumble 	I could be scumbling
you could be scumbling
he could be scumbling
we could be scumbling
you could be scumbling
they could be scumbling	I could have scumbled
you could have scumbled
he could have scumbled
we could have scumbled
you could have scumbled
they could have scumbled	I could have been scumbling
you could have been scumbling
he could have been scumbling
we could have been scumbling
you could have been scumbling
they could have been scumbling	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't scumble
you couldn't scumble
he couldn't scumble
we couldn't scumble
you couldn't scumble
they couldn't scumble 	I couldn't be scumbling
you couldn't be scumbling
he couldn't be scumbling
we couldn't be scumbling
you couldn't be scumbling
they couldn't be scumbling	I couldn't have scumbled
you couldn't have scumbled
he couldn't have scumbled
we couldn't have scumbled
you couldn't have scumbled
they couldn't have scumbled	I couldn't have been scumbling
you couldn't have been scumbling
he couldn't have been scumbling
we couldn't have been scumbling
you couldn't have been scumbling
they couldn't have been scumbling	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I scumble?
could you scumble?
could he scumble?
could we scumble?
could you scumble?
could they scumble? 	could I be scumbling?
could you be scumbling?
could he be scumbling?
could we be scumbling?
could you be scumbling?
could they be scumbling? 	could I have scumbled?
could you have scumbled?
could he have scumbled?
could we have scumbled?
could you have scumbled?
could they have scumbled? 	could I have been scumbling?
could you have been scumbling?
could he have been scumbling?
could we have been scumbling?
could you have been scumbling?
could they have been scumbling? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I scumble?
couldn't you scumble?
couldn't he scumble?
couldn't we scumble?
couldn't you scumble?
couldn't they scumble? 	couldn't I be scumbling?
couldn't you be scumbling?
couldn't he be scumbling?
couldn't we be scumbling?
couldn't you be scumbling?
couldn't they be scumbling? 	couldn't I have scumbled?
couldn't you have scumbled?
couldn't he have scumbled?
couldn't we have scumbled?
couldn't you have scumbled?
couldn't they have scumbled? 	couldn't I have been scumbling?
couldn't you have been scumbling?
couldn't he have been scumbling?
couldn't we have been scumbling?
couldn't you have been scumbling?
couldn't they have been scumbling?