could invaginate
Regular verb: invaginate - invaginated- invaginated

Affirmation 	
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I could invaginate
you could invaginate
he could invaginate
we could invaginate
you could invaginate
they could invaginate 	I could be invaginating
you could be invaginating
he could be invaginating
we could be invaginating
you could be invaginating
they could be invaginating	I could have invaginated
you could have invaginated
he could have invaginated
we could have invaginated
you could have invaginated
they could have invaginated	I could have been invaginating
you could have been invaginating
he could have been invaginating
we could have been invaginating
you could have been invaginating
they could have been invaginating	

Negation 	
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I couldn't invaginate
you couldn't invaginate
he couldn't invaginate
we couldn't invaginate
you couldn't invaginate
they couldn't invaginate 	I couldn't be invaginating
you couldn't be invaginating
he couldn't be invaginating
we couldn't be invaginating
you couldn't be invaginating
they couldn't be invaginating	I couldn't have invaginated
you couldn't have invaginated
he couldn't have invaginated
we couldn't have invaginated
you couldn't have invaginated
they couldn't have invaginated	I couldn't have been invaginating
you couldn't have been invaginating
he couldn't have been invaginating
we couldn't have been invaginating
you couldn't have been invaginating
they couldn't have been invaginating	

Interrogative form 	
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could I invaginate?
could you invaginate?
could he invaginate?
could we invaginate?
could you invaginate?
could they invaginate? 	could I be invaginating?
could you be invaginating?
could he be invaginating?
could we be invaginating?
could you be invaginating?
could they be invaginating? 	could I have invaginated?
could you have invaginated?
could he have invaginated?
could we have invaginated?
could you have invaginated?
could they have invaginated? 	could I have been invaginating?
could you have been invaginating?
could he have been invaginating?
could we have been invaginating?
could you have been invaginating?
could they have been invaginating? 	

Interro-negative form 	
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couldn't I invaginate?
couldn't you invaginate?
couldn't he invaginate?
couldn't we invaginate?
couldn't you invaginate?
couldn't they invaginate? 	couldn't I be invaginating?
couldn't you be invaginating?
couldn't he be invaginating?
couldn't we be invaginating?
couldn't you be invaginating?
couldn't they be invaginating? 	couldn't I have invaginated?
couldn't you have invaginated?
couldn't he have invaginated?
couldn't we have invaginated?
couldn't you have invaginated?
couldn't they have invaginated? 	couldn't I have been invaginating?
couldn't you have been invaginating?
couldn't he have been invaginating?
couldn't we have been invaginating?
couldn't you have been invaginating?
couldn't they have been invaginating?