could pong
Regular verb: pong - ponged- ponged

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could pong
you could pong
she could pong
we could pong
you could pong
they could pong 	I could be ponging
you could be ponging
she could be ponging
we could be ponging
you could be ponging
they could be ponging	I could have ponged
you could have ponged
she could have ponged
we could have ponged
you could have ponged
they could have ponged	I could have been ponging
you could have been ponging
she could have been ponging
we could have been ponging
you could have been ponging
they could have been ponging	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't pong
you couldn't pong
she couldn't pong
we couldn't pong
you couldn't pong
they couldn't pong 	I couldn't be ponging
you couldn't be ponging
she couldn't be ponging
we couldn't be ponging
you couldn't be ponging
they couldn't be ponging	I couldn't have ponged
you couldn't have ponged
she couldn't have ponged
we couldn't have ponged
you couldn't have ponged
they couldn't have ponged	I couldn't have been ponging
you couldn't have been ponging
she couldn't have been ponging
we couldn't have been ponging
you couldn't have been ponging
they couldn't have been ponging	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I pong?
could you pong?
could she pong?
could we pong?
could you pong?
could they pong? 	could I be ponging?
could you be ponging?
could she be ponging?
could we be ponging?
could you be ponging?
could they be ponging? 	could I have ponged?
could you have ponged?
could she have ponged?
could we have ponged?
could you have ponged?
could they have ponged? 	could I have been ponging?
could you have been ponging?
could she have been ponging?
could we have been ponging?
could you have been ponging?
could they have been ponging? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I pong?
couldn't you pong?
couldn't she pong?
couldn't we pong?
couldn't you pong?
couldn't they pong? 	couldn't I be ponging?
couldn't you be ponging?
couldn't she be ponging?
couldn't we be ponging?
couldn't you be ponging?
couldn't they be ponging? 	couldn't I have ponged?
couldn't you have ponged?
couldn't she have ponged?
couldn't we have ponged?
couldn't you have ponged?
couldn't they have ponged? 	couldn't I have been ponging?
couldn't you have been ponging?
couldn't she have been ponging?
couldn't we have been ponging?
couldn't you have been ponging?
couldn't they have been ponging?