could flash
Regular verb: flash - flashed- flashed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could flash
you could flash
she could flash
we could flash
you could flash
they could flash 	I could be flashing
you could be flashing
she could be flashing
we could be flashing
you could be flashing
they could be flashing	I could have flashed
you could have flashed
she could have flashed
we could have flashed
you could have flashed
they could have flashed	I could have been flashing
you could have been flashing
she could have been flashing
we could have been flashing
you could have been flashing
they could have been flashing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not flash
you could not flash
she could not flash
we could not flash
you could not flash
they could not flash 	I could not be flashing
you could not be flashing
she could not be flashing
we could not be flashing
you could not be flashing
they could not be flashing	I could not have flashed
you could not have flashed
she could not have flashed
we could not have flashed
you could not have flashed
they could not have flashed	I could not have been flashing
you could not have been flashing
she could not have been flashing
we could not have been flashing
you could not have been flashing
they could not have been flashing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I flash?
could you flash?
could she flash?
could we flash?
could you flash?
could they flash? 	could I be flashing?
could you be flashing?
could she be flashing?
could we be flashing?
could you be flashing?
could they be flashing? 	could I have flashed?
could you have flashed?
could she have flashed?
could we have flashed?
could you have flashed?
could they have flashed? 	could I have been flashing?
could you have been flashing?
could she have been flashing?
could we have been flashing?
could you have been flashing?
could they have been flashing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not flash?
could you not flash?
could she not flash?
could we not flash?
could you not flash?
could they not flash? 	could I not be flashing?
could you not be flashing?
could she not be flashing?
could we not be flashing?
could you not be flashing?
could they not be flashing? 	could I not have flashed?
could you not have flashed?
could she not have flashed?
could we not have flashed?
could you not have flashed?
could they not have flashed? 	could I not have been flashing?
could you not have been flashing?
could she not have been flashing?
could we not have been flashing?
could you not have been flashing?
could they not have been flashing?