could fribble
Regular verb: fribble - fribbled- fribbled

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could fribble
you could fribble
he could fribble
we could fribble
you could fribble
they could fribble 	I could be fribbling
you could be fribbling
he could be fribbling
we could be fribbling
you could be fribbling
they could be fribbling	I could have fribbled
you could have fribbled
he could have fribbled
we could have fribbled
you could have fribbled
they could have fribbled	I could have been fribbling
you could have been fribbling
he could have been fribbling
we could have been fribbling
you could have been fribbling
they could have been fribbling	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not fribble
you could not fribble
he could not fribble
we could not fribble
you could not fribble
they could not fribble 	I could not be fribbling
you could not be fribbling
he could not be fribbling
we could not be fribbling
you could not be fribbling
they could not be fribbling	I could not have fribbled
you could not have fribbled
he could not have fribbled
we could not have fribbled
you could not have fribbled
they could not have fribbled	I could not have been fribbling
you could not have been fribbling
he could not have been fribbling
we could not have been fribbling
you could not have been fribbling
they could not have been fribbling	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I fribble?
could you fribble?
could he fribble?
could we fribble?
could you fribble?
could they fribble? 	could I be fribbling?
could you be fribbling?
could he be fribbling?
could we be fribbling?
could you be fribbling?
could they be fribbling? 	could I have fribbled?
could you have fribbled?
could he have fribbled?
could we have fribbled?
could you have fribbled?
could they have fribbled? 	could I have been fribbling?
could you have been fribbling?
could he have been fribbling?
could we have been fribbling?
could you have been fribbling?
could they have been fribbling? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not fribble?
could you not fribble?
could he not fribble?
could we not fribble?
could you not fribble?
could they not fribble? 	could I not be fribbling?
could you not be fribbling?
could he not be fribbling?
could we not be fribbling?
could you not be fribbling?
could they not be fribbling? 	could I not have fribbled?
could you not have fribbled?
could he not have fribbled?
could we not have fribbled?
could you not have fribbled?
could they not have fribbled? 	could I not have been fribbling?
could you not have been fribbling?
could he not have been fribbling?
could we not have been fribbling?
could you not have been fribbling?
could they not have been fribbling?