could giggle
Regular verb: giggle - giggled- giggled

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could giggle
you could giggle
he could giggle
we could giggle
you could giggle
they could giggle 	I could be giggling
you could be giggling
he could be giggling
we could be giggling
you could be giggling
they could be giggling	I could have giggled
you could have giggled
he could have giggled
we could have giggled
you could have giggled
they could have giggled	I could have been giggling
you could have been giggling
he could have been giggling
we could have been giggling
you could have been giggling
they could have been giggling	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not giggle
you could not giggle
he could not giggle
we could not giggle
you could not giggle
they could not giggle 	I could not be giggling
you could not be giggling
he could not be giggling
we could not be giggling
you could not be giggling
they could not be giggling	I could not have giggled
you could not have giggled
he could not have giggled
we could not have giggled
you could not have giggled
they could not have giggled	I could not have been giggling
you could not have been giggling
he could not have been giggling
we could not have been giggling
you could not have been giggling
they could not have been giggling	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I giggle?
could you giggle?
could he giggle?
could we giggle?
could you giggle?
could they giggle? 	could I be giggling?
could you be giggling?
could he be giggling?
could we be giggling?
could you be giggling?
could they be giggling? 	could I have giggled?
could you have giggled?
could he have giggled?
could we have giggled?
could you have giggled?
could they have giggled? 	could I have been giggling?
could you have been giggling?
could he have been giggling?
could we have been giggling?
could you have been giggling?
could they have been giggling? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not giggle?
could you not giggle?
could he not giggle?
could we not giggle?
could you not giggle?
could they not giggle? 	could I not be giggling?
could you not be giggling?
could he not be giggling?
could we not be giggling?
could you not be giggling?
could they not be giggling? 	could I not have giggled?
could you not have giggled?
could he not have giggled?
could we not have giggled?
could you not have giggled?
could they not have giggled? 	could I not have been giggling?
could you not have been giggling?
could he not have been giggling?
could we not have been giggling?
could you not have been giggling?
could they not have been giggling?