could erect
Regular verb: erect - erected- erected

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could erect
you could erect
she could erect
we could erect
you could erect
they could erect 	I could be erecting
you could be erecting
she could be erecting
we could be erecting
you could be erecting
they could be erecting	I could have erected
you could have erected
she could have erected
we could have erected
you could have erected
they could have erected	I could have been erecting
you could have been erecting
she could have been erecting
we could have been erecting
you could have been erecting
they could have been erecting	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't erect
you couldn't erect
she couldn't erect
we couldn't erect
you couldn't erect
they couldn't erect 	I couldn't be erecting
you couldn't be erecting
she couldn't be erecting
we couldn't be erecting
you couldn't be erecting
they couldn't be erecting	I couldn't have erected
you couldn't have erected
she couldn't have erected
we couldn't have erected
you couldn't have erected
they couldn't have erected	I couldn't have been erecting
you couldn't have been erecting
she couldn't have been erecting
we couldn't have been erecting
you couldn't have been erecting
they couldn't have been erecting	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I erect?
could you erect?
could she erect?
could we erect?
could you erect?
could they erect? 	could I be erecting?
could you be erecting?
could she be erecting?
could we be erecting?
could you be erecting?
could they be erecting? 	could I have erected?
could you have erected?
could she have erected?
could we have erected?
could you have erected?
could they have erected? 	could I have been erecting?
could you have been erecting?
could she have been erecting?
could we have been erecting?
could you have been erecting?
could they have been erecting? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I erect?
couldn't you erect?
couldn't she erect?
couldn't we erect?
couldn't you erect?
couldn't they erect? 	couldn't I be erecting?
couldn't you be erecting?
couldn't she be erecting?
couldn't we be erecting?
couldn't you be erecting?
couldn't they be erecting? 	couldn't I have erected?
couldn't you have erected?
couldn't she have erected?
couldn't we have erected?
couldn't you have erected?
couldn't they have erected? 	couldn't I have been erecting?
couldn't you have been erecting?
couldn't she have been erecting?
couldn't we have been erecting?
couldn't you have been erecting?
couldn't they have been erecting?