could zing
Regular verb: zing - zinged- zinged

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could zing
you could zing
he could zing
we could zing
you could zing
they could zing 	I could be zinging
you could be zinging
he could be zinging
we could be zinging
you could be zinging
they could be zinging	I could have zinged
you could have zinged
he could have zinged
we could have zinged
you could have zinged
they could have zinged	I could have been zinging
you could have been zinging
he could have been zinging
we could have been zinging
you could have been zinging
they could have been zinging	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not zing
you could not zing
he could not zing
we could not zing
you could not zing
they could not zing 	I could not be zinging
you could not be zinging
he could not be zinging
we could not be zinging
you could not be zinging
they could not be zinging	I could not have zinged
you could not have zinged
he could not have zinged
we could not have zinged
you could not have zinged
they could not have zinged	I could not have been zinging
you could not have been zinging
he could not have been zinging
we could not have been zinging
you could not have been zinging
they could not have been zinging	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I zing?
could you zing?
could he zing?
could we zing?
could you zing?
could they zing? 	could I be zinging?
could you be zinging?
could he be zinging?
could we be zinging?
could you be zinging?
could they be zinging? 	could I have zinged?
could you have zinged?
could he have zinged?
could we have zinged?
could you have zinged?
could they have zinged? 	could I have been zinging?
could you have been zinging?
could he have been zinging?
could we have been zinging?
could you have been zinging?
could they have been zinging? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not zing?
could you not zing?
could he not zing?
could we not zing?
could you not zing?
could they not zing? 	could I not be zinging?
could you not be zinging?
could he not be zinging?
could we not be zinging?
could you not be zinging?
could they not be zinging? 	could I not have zinged?
could you not have zinged?
could he not have zinged?
could we not have zinged?
could you not have zinged?
could they not have zinged? 	could I not have been zinging?
could you not have been zinging?
could he not have been zinging?
could we not have been zinging?
could you not have been zinging?
could they not have been zinging?