could burp
Regular verb: burp - burped- burped

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could burp
you could burp
she could burp
we could burp
you could burp
they could burp 	I could be burping
you could be burping
she could be burping
we could be burping
you could be burping
they could be burping	I could have burped
you could have burped
she could have burped
we could have burped
you could have burped
they could have burped	I could have been burping
you could have been burping
she could have been burping
we could have been burping
you could have been burping
they could have been burping	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not burp
you could not burp
she could not burp
we could not burp
you could not burp
they could not burp 	I could not be burping
you could not be burping
she could not be burping
we could not be burping
you could not be burping
they could not be burping	I could not have burped
you could not have burped
she could not have burped
we could not have burped
you could not have burped
they could not have burped	I could not have been burping
you could not have been burping
she could not have been burping
we could not have been burping
you could not have been burping
they could not have been burping	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I burp?
could you burp?
could she burp?
could we burp?
could you burp?
could they burp? 	could I be burping?
could you be burping?
could she be burping?
could we be burping?
could you be burping?
could they be burping? 	could I have burped?
could you have burped?
could she have burped?
could we have burped?
could you have burped?
could they have burped? 	could I have been burping?
could you have been burping?
could she have been burping?
could we have been burping?
could you have been burping?
could they have been burping? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not burp?
could you not burp?
could she not burp?
could we not burp?
could you not burp?
could they not burp? 	could I not be burping?
could you not be burping?
could she not be burping?
could we not be burping?
could you not be burping?
could they not be burping? 	could I not have burped?
could you not have burped?
could she not have burped?
could we not have burped?
could you not have burped?
could they not have burped? 	could I not have been burping?
could you not have been burping?
could she not have been burping?
could we not have been burping?
could you not have been burping?
could they not have been burping?