could interface
Regular verb: interface - interfaced- interfaced

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could interface
you could interface
she could interface
we could interface
you could interface
they could interface 	I could be interfacing
you could be interfacing
she could be interfacing
we could be interfacing
you could be interfacing
they could be interfacing	I could have interfaced
you could have interfaced
she could have interfaced
we could have interfaced
you could have interfaced
they could have interfaced	I could have been interfacing
you could have been interfacing
she could have been interfacing
we could have been interfacing
you could have been interfacing
they could have been interfacing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not interface
you could not interface
she could not interface
we could not interface
you could not interface
they could not interface 	I could not be interfacing
you could not be interfacing
she could not be interfacing
we could not be interfacing
you could not be interfacing
they could not be interfacing	I could not have interfaced
you could not have interfaced
she could not have interfaced
we could not have interfaced
you could not have interfaced
they could not have interfaced	I could not have been interfacing
you could not have been interfacing
she could not have been interfacing
we could not have been interfacing
you could not have been interfacing
they could not have been interfacing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I interface?
could you interface?
could she interface?
could we interface?
could you interface?
could they interface? 	could I be interfacing?
could you be interfacing?
could she be interfacing?
could we be interfacing?
could you be interfacing?
could they be interfacing? 	could I have interfaced?
could you have interfaced?
could she have interfaced?
could we have interfaced?
could you have interfaced?
could they have interfaced? 	could I have been interfacing?
could you have been interfacing?
could she have been interfacing?
could we have been interfacing?
could you have been interfacing?
could they have been interfacing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not interface?
could you not interface?
could she not interface?
could we not interface?
could you not interface?
could they not interface? 	could I not be interfacing?
could you not be interfacing?
could she not be interfacing?
could we not be interfacing?
could you not be interfacing?
could they not be interfacing? 	could I not have interfaced?
could you not have interfaced?
could she not have interfaced?
could we not have interfaced?
could you not have interfaced?
could they not have interfaced? 	could I not have been interfacing?
could you not have been interfacing?
could she not have been interfacing?
could we not have been interfacing?
could you not have been interfacing?
could they not have been interfacing?