could pith
Regular verb: pith - pithed- pithed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could pith
you could pith
she could pith
we could pith
you could pith
they could pith 	I could be pithing
you could be pithing
she could be pithing
we could be pithing
you could be pithing
they could be pithing	I could have pithed
you could have pithed
she could have pithed
we could have pithed
you could have pithed
they could have pithed	I could have been pithing
you could have been pithing
she could have been pithing
we could have been pithing
you could have been pithing
they could have been pithing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not pith
you could not pith
she could not pith
we could not pith
you could not pith
they could not pith 	I could not be pithing
you could not be pithing
she could not be pithing
we could not be pithing
you could not be pithing
they could not be pithing	I could not have pithed
you could not have pithed
she could not have pithed
we could not have pithed
you could not have pithed
they could not have pithed	I could not have been pithing
you could not have been pithing
she could not have been pithing
we could not have been pithing
you could not have been pithing
they could not have been pithing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I pith?
could you pith?
could she pith?
could we pith?
could you pith?
could they pith? 	could I be pithing?
could you be pithing?
could she be pithing?
could we be pithing?
could you be pithing?
could they be pithing? 	could I have pithed?
could you have pithed?
could she have pithed?
could we have pithed?
could you have pithed?
could they have pithed? 	could I have been pithing?
could you have been pithing?
could she have been pithing?
could we have been pithing?
could you have been pithing?
could they have been pithing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not pith?
could you not pith?
could she not pith?
could we not pith?
could you not pith?
could they not pith? 	could I not be pithing?
could you not be pithing?
could she not be pithing?
could we not be pithing?
could you not be pithing?
could they not be pithing? 	could I not have pithed?
could you not have pithed?
could she not have pithed?
could we not have pithed?
could you not have pithed?
could they not have pithed? 	could I not have been pithing?
could you not have been pithing?
could she not have been pithing?
could we not have been pithing?
could you not have been pithing?
could they not have been pithing?