English verb conjugation
COULD APPEAR

Regular verb: appear - appeared - appeared

Affirmation

Simple form	V-ing form
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
Perfect	V-ing perfect
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
I couldn't appear you couldn't appear he couldn't appear we couldn't appear you couldn't appear they couldn't appear	I couldn't be appearing you couldn't be appearing he couldn't be appearing we couldn't be appearing you couldn't be appearing they couldn't be appearing
Perfect	V-ing perfect
I couldn't have appeared you couldn't have appeared he couldn't have appeared we couldn't have appeared you couldn't have appeared they couldn't have appeared	I couldn't have been appearing you couldn't have been appearing he couldn't have been appearing we couldn't have been appearing you couldn't have been appearing they couldn't have been appearing

Interrogative form

Simple form	V-ing form
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?
Perfect	V-ing perfect
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
couldn't I appear? couldn't you appear? couldn't he appear? couldn't we appear? couldn't you appear? couldn't they appear?	couldn't I be appearing? couldn't you be appearing? couldn't he be appearing? couldn't we be appearing? couldn't you be appearing? couldn't they be appearing?
Perfect	V-ing perfect
couldn't I have appeared? couldn't you have appeared? couldn't he have appeared? couldn't we have appeared? couldn't you have appeared? couldn't they have appeared?	couldn't I have been appearing? couldn't you have been appearing? couldn't he have been appearing? couldn't we have been appearing? couldn't you have been appearing? couldn't they have been appearing?