could preguarantee
Regular verb: preguarantee - preguaranteed- preguaranteed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could preguarantee
you could preguarantee
he could preguarantee
we could preguarantee
you could preguarantee
they could preguarantee 	I could be preguaranteeing
you could be preguaranteeing
he could be preguaranteeing
we could be preguaranteeing
you could be preguaranteeing
they could be preguaranteeing	I could have preguaranteed
you could have preguaranteed
he could have preguaranteed
we could have preguaranteed
you could have preguaranteed
they could have preguaranteed	I could have been preguaranteeing
you could have been preguaranteeing
he could have been preguaranteeing
we could have been preguaranteeing
you could have been preguaranteeing
they could have been preguaranteeing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't preguarantee
you couldn't preguarantee
he couldn't preguarantee
we couldn't preguarantee
you couldn't preguarantee
they couldn't preguarantee 	I couldn't be preguaranteeing
you couldn't be preguaranteeing
he couldn't be preguaranteeing
we couldn't be preguaranteeing
you couldn't be preguaranteeing
they couldn't be preguaranteeing	I couldn't have preguaranteed
you couldn't have preguaranteed
he couldn't have preguaranteed
we couldn't have preguaranteed
you couldn't have preguaranteed
they couldn't have preguaranteed	I couldn't have been preguaranteeing
you couldn't have been preguaranteeing
he couldn't have been preguaranteeing
we couldn't have been preguaranteeing
you couldn't have been preguaranteeing
they couldn't have been preguaranteeing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I preguarantee?
could you preguarantee?
could he preguarantee?
could we preguarantee?
could you preguarantee?
could they preguarantee? 	could I be preguaranteeing?
could you be preguaranteeing?
could he be preguaranteeing?
could we be preguaranteeing?
could you be preguaranteeing?
could they be preguaranteeing? 	could I have preguaranteed?
could you have preguaranteed?
could he have preguaranteed?
could we have preguaranteed?
could you have preguaranteed?
could they have preguaranteed? 	could I have been preguaranteeing?
could you have been preguaranteeing?
could he have been preguaranteeing?
could we have been preguaranteeing?
could you have been preguaranteeing?
could they have been preguaranteeing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I preguarantee?
couldn't you preguarantee?
couldn't he preguarantee?
couldn't we preguarantee?
couldn't you preguarantee?
couldn't they preguarantee? 	couldn't I be preguaranteeing?
couldn't you be preguaranteeing?
couldn't he be preguaranteeing?
couldn't we be preguaranteeing?
couldn't you be preguaranteeing?
couldn't they be preguaranteeing? 	couldn't I have preguaranteed?
couldn't you have preguaranteed?
couldn't he have preguaranteed?
couldn't we have preguaranteed?
couldn't you have preguaranteed?
couldn't they have preguaranteed? 	couldn't I have been preguaranteeing?
couldn't you have been preguaranteeing?
couldn't he have been preguaranteeing?
couldn't we have been preguaranteeing?
couldn't you have been preguaranteeing?
couldn't they have been preguaranteeing?