could appear
Regular verb: appear - appeared- appeared

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could appear
you could appear
he could appear
we could appear
you could appear
they could appear 	I could be appearing
you could be appearing
he could be appearing
we could be appearing
you could be appearing
they could be appearing	I could have appeared
you could have appeared
he could have appeared
we could have appeared
you could have appeared
they could have appeared	I could have been appearing
you could have been appearing
he could have been appearing
we could have been appearing
you could have been appearing
they could have been appearing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not appear
you could not appear
he could not appear
we could not appear
you could not appear
they could not appear 	I could not be appearing
you could not be appearing
he could not be appearing
we could not be appearing
you could not be appearing
they could not be appearing	I could not have appeared
you could not have appeared
he could not have appeared
we could not have appeared
you could not have appeared
they could not have appeared	I could not have been appearing
you could not have been appearing
he could not have been appearing
we could not have been appearing
you could not have been appearing
they could not have been appearing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I appear?
could you appear?
could he appear?
could we appear?
could you appear?
could they appear? 	could I be appearing?
could you be appearing?
could he be appearing?
could we be appearing?
could you be appearing?
could they be appearing? 	could I have appeared?
could you have appeared?
could he have appeared?
could we have appeared?
could you have appeared?
could they have appeared? 	could I have been appearing?
could you have been appearing?
could he have been appearing?
could we have been appearing?
could you have been appearing?
could they have been appearing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not appear?
could you not appear?
could he not appear?
could we not appear?
could you not appear?
could they not appear? 	could I not be appearing?
could you not be appearing?
could he not be appearing?
could we not be appearing?
could you not be appearing?
could they not be appearing? 	could I not have appeared?
could you not have appeared?
could he not have appeared?
could we not have appeared?
could you not have appeared?
could they not have appeared? 	could I not have been appearing?
could you not have been appearing?
could he not have been appearing?
could we not have been appearing?
could you not have been appearing?
could they not have been appearing?