could vanish
Regular verb: vanish - vanished- vanished

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could vanish
you could vanish
she could vanish
we could vanish
you could vanish
they could vanish 	I could be vanishing
you could be vanishing
she could be vanishing
we could be vanishing
you could be vanishing
they could be vanishing	I could have vanished
you could have vanished
she could have vanished
we could have vanished
you could have vanished
they could have vanished	I could have been vanishing
you could have been vanishing
she could have been vanishing
we could have been vanishing
you could have been vanishing
they could have been vanishing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't vanish
you couldn't vanish
she couldn't vanish
we couldn't vanish
you couldn't vanish
they couldn't vanish 	I couldn't be vanishing
you couldn't be vanishing
she couldn't be vanishing
we couldn't be vanishing
you couldn't be vanishing
they couldn't be vanishing	I couldn't have vanished
you couldn't have vanished
she couldn't have vanished
we couldn't have vanished
you couldn't have vanished
they couldn't have vanished	I couldn't have been vanishing
you couldn't have been vanishing
she couldn't have been vanishing
we couldn't have been vanishing
you couldn't have been vanishing
they couldn't have been vanishing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I vanish?
could you vanish?
could she vanish?
could we vanish?
could you vanish?
could they vanish? 	could I be vanishing?
could you be vanishing?
could she be vanishing?
could we be vanishing?
could you be vanishing?
could they be vanishing? 	could I have vanished?
could you have vanished?
could she have vanished?
could we have vanished?
could you have vanished?
could they have vanished? 	could I have been vanishing?
could you have been vanishing?
could she have been vanishing?
could we have been vanishing?
could you have been vanishing?
could they have been vanishing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I vanish?
couldn't you vanish?
couldn't she vanish?
couldn't we vanish?
couldn't you vanish?
couldn't they vanish? 	couldn't I be vanishing?
couldn't you be vanishing?
couldn't she be vanishing?
couldn't we be vanishing?
couldn't you be vanishing?
couldn't they be vanishing? 	couldn't I have vanished?
couldn't you have vanished?
couldn't she have vanished?
couldn't we have vanished?
couldn't you have vanished?
couldn't they have vanished? 	couldn't I have been vanishing?
couldn't you have been vanishing?
couldn't she have been vanishing?
couldn't we have been vanishing?
couldn't you have been vanishing?
couldn't they have been vanishing?