could triangulate
Regular verb: triangulate - triangulated- triangulated

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could triangulate
you could triangulate
she could triangulate
we could triangulate
you could triangulate
they could triangulate 	I could be triangulating
you could be triangulating
she could be triangulating
we could be triangulating
you could be triangulating
they could be triangulating	I could have triangulated
you could have triangulated
she could have triangulated
we could have triangulated
you could have triangulated
they could have triangulated	I could have been triangulating
you could have been triangulating
she could have been triangulating
we could have been triangulating
you could have been triangulating
they could have been triangulating	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't triangulate
you couldn't triangulate
she couldn't triangulate
we couldn't triangulate
you couldn't triangulate
they couldn't triangulate 	I couldn't be triangulating
you couldn't be triangulating
she couldn't be triangulating
we couldn't be triangulating
you couldn't be triangulating
they couldn't be triangulating	I couldn't have triangulated
you couldn't have triangulated
she couldn't have triangulated
we couldn't have triangulated
you couldn't have triangulated
they couldn't have triangulated	I couldn't have been triangulating
you couldn't have been triangulating
she couldn't have been triangulating
we couldn't have been triangulating
you couldn't have been triangulating
they couldn't have been triangulating	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I triangulate?
could you triangulate?
could she triangulate?
could we triangulate?
could you triangulate?
could they triangulate? 	could I be triangulating?
could you be triangulating?
could she be triangulating?
could we be triangulating?
could you be triangulating?
could they be triangulating? 	could I have triangulated?
could you have triangulated?
could she have triangulated?
could we have triangulated?
could you have triangulated?
could they have triangulated? 	could I have been triangulating?
could you have been triangulating?
could she have been triangulating?
could we have been triangulating?
could you have been triangulating?
could they have been triangulating? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I triangulate?
couldn't you triangulate?
couldn't she triangulate?
couldn't we triangulate?
couldn't you triangulate?
couldn't they triangulate? 	couldn't I be triangulating?
couldn't you be triangulating?
couldn't she be triangulating?
couldn't we be triangulating?
couldn't you be triangulating?
couldn't they be triangulating? 	couldn't I have triangulated?
couldn't you have triangulated?
couldn't she have triangulated?
couldn't we have triangulated?
couldn't you have triangulated?
couldn't they have triangulated? 	couldn't I have been triangulating?
couldn't you have been triangulating?
couldn't she have been triangulating?
couldn't we have been triangulating?
couldn't you have been triangulating?
couldn't they have been triangulating?