could interleave
Regular verb: interleave - interleaved- interleaved

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could interleave
you could interleave
she could interleave
we could interleave
you could interleave
they could interleave 	I could be interleaving
you could be interleaving
she could be interleaving
we could be interleaving
you could be interleaving
they could be interleaving	I could have interleaved
you could have interleaved
she could have interleaved
we could have interleaved
you could have interleaved
they could have interleaved	I could have been interleaving
you could have been interleaving
she could have been interleaving
we could have been interleaving
you could have been interleaving
they could have been interleaving	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't interleave
you couldn't interleave
she couldn't interleave
we couldn't interleave
you couldn't interleave
they couldn't interleave 	I couldn't be interleaving
you couldn't be interleaving
she couldn't be interleaving
we couldn't be interleaving
you couldn't be interleaving
they couldn't be interleaving	I couldn't have interleaved
you couldn't have interleaved
she couldn't have interleaved
we couldn't have interleaved
you couldn't have interleaved
they couldn't have interleaved	I couldn't have been interleaving
you couldn't have been interleaving
she couldn't have been interleaving
we couldn't have been interleaving
you couldn't have been interleaving
they couldn't have been interleaving	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I interleave?
could you interleave?
could she interleave?
could we interleave?
could you interleave?
could they interleave? 	could I be interleaving?
could you be interleaving?
could she be interleaving?
could we be interleaving?
could you be interleaving?
could they be interleaving? 	could I have interleaved?
could you have interleaved?
could she have interleaved?
could we have interleaved?
could you have interleaved?
could they have interleaved? 	could I have been interleaving?
could you have been interleaving?
could she have been interleaving?
could we have been interleaving?
could you have been interleaving?
could they have been interleaving? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I interleave?
couldn't you interleave?
couldn't she interleave?
couldn't we interleave?
couldn't you interleave?
couldn't they interleave? 	couldn't I be interleaving?
couldn't you be interleaving?
couldn't she be interleaving?
couldn't we be interleaving?
couldn't you be interleaving?
couldn't they be interleaving? 	couldn't I have interleaved?
couldn't you have interleaved?
couldn't she have interleaved?
couldn't we have interleaved?
couldn't you have interleaved?
couldn't they have interleaved? 	couldn't I have been interleaving?
couldn't you have been interleaving?
couldn't she have been interleaving?
couldn't we have been interleaving?
couldn't you have been interleaving?
couldn't they have been interleaving?