could litter
Regular verb: litter - littered- littered

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could litter
you could litter
he could litter
we could litter
you could litter
they could litter 	I could be littering
you could be littering
he could be littering
we could be littering
you could be littering
they could be littering	I could have littered
you could have littered
he could have littered
we could have littered
you could have littered
they could have littered	I could have been littering
you could have been littering
he could have been littering
we could have been littering
you could have been littering
they could have been littering	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not litter
you could not litter
he could not litter
we could not litter
you could not litter
they could not litter 	I could not be littering
you could not be littering
he could not be littering
we could not be littering
you could not be littering
they could not be littering	I could not have littered
you could not have littered
he could not have littered
we could not have littered
you could not have littered
they could not have littered	I could not have been littering
you could not have been littering
he could not have been littering
we could not have been littering
you could not have been littering
they could not have been littering	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I litter?
could you litter?
could he litter?
could we litter?
could you litter?
could they litter? 	could I be littering?
could you be littering?
could he be littering?
could we be littering?
could you be littering?
could they be littering? 	could I have littered?
could you have littered?
could he have littered?
could we have littered?
could you have littered?
could they have littered? 	could I have been littering?
could you have been littering?
could he have been littering?
could we have been littering?
could you have been littering?
could they have been littering? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not litter?
could you not litter?
could he not litter?
could we not litter?
could you not litter?
could they not litter? 	could I not be littering?
could you not be littering?
could he not be littering?
could we not be littering?
could you not be littering?
could they not be littering? 	could I not have littered?
could you not have littered?
could he not have littered?
could we not have littered?
could you not have littered?
could they not have littered? 	could I not have been littering?
could you not have been littering?
could he not have been littering?
could we not have been littering?
could you not have been littering?
could they not have been littering?