could whitewash
Regular verb: whitewash - whitewashed- whitewashed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could whitewash
you could whitewash
he could whitewash
we could whitewash
you could whitewash
they could whitewash 	I could be whitewashing
you could be whitewashing
he could be whitewashing
we could be whitewashing
you could be whitewashing
they could be whitewashing	I could have whitewashed
you could have whitewashed
he could have whitewashed
we could have whitewashed
you could have whitewashed
they could have whitewashed	I could have been whitewashing
you could have been whitewashing
he could have been whitewashing
we could have been whitewashing
you could have been whitewashing
they could have been whitewashing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not whitewash
you could not whitewash
he could not whitewash
we could not whitewash
you could not whitewash
they could not whitewash 	I could not be whitewashing
you could not be whitewashing
he could not be whitewashing
we could not be whitewashing
you could not be whitewashing
they could not be whitewashing	I could not have whitewashed
you could not have whitewashed
he could not have whitewashed
we could not have whitewashed
you could not have whitewashed
they could not have whitewashed	I could not have been whitewashing
you could not have been whitewashing
he could not have been whitewashing
we could not have been whitewashing
you could not have been whitewashing
they could not have been whitewashing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I whitewash?
could you whitewash?
could he whitewash?
could we whitewash?
could you whitewash?
could they whitewash? 	could I be whitewashing?
could you be whitewashing?
could he be whitewashing?
could we be whitewashing?
could you be whitewashing?
could they be whitewashing? 	could I have whitewashed?
could you have whitewashed?
could he have whitewashed?
could we have whitewashed?
could you have whitewashed?
could they have whitewashed? 	could I have been whitewashing?
could you have been whitewashing?
could he have been whitewashing?
could we have been whitewashing?
could you have been whitewashing?
could they have been whitewashing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not whitewash?
could you not whitewash?
could he not whitewash?
could we not whitewash?
could you not whitewash?
could they not whitewash? 	could I not be whitewashing?
could you not be whitewashing?
could he not be whitewashing?
could we not be whitewashing?
could you not be whitewashing?
could they not be whitewashing? 	could I not have whitewashed?
could you not have whitewashed?
could he not have whitewashed?
could we not have whitewashed?
could you not have whitewashed?
could they not have whitewashed? 	could I not have been whitewashing?
could you not have been whitewashing?
could he not have been whitewashing?
could we not have been whitewashing?
could you not have been whitewashing?
could they not have been whitewashing?