English verb conjugation
COULD RAREFY

Regular verb: rarefy - rarefied - rarefied

Affirmation

Simple form	V-ing form
I could rarefy you could rarefy he could rarefy we could rarefy you could rarefy they could rarefy	I could be rarefying you could be rarefying he could be rarefying we could be rarefying you could be rarefying they could be rarefying
Perfect	V-ing perfect
I could have rarefied you could have rarefied he could have rarefied we could have rarefied you could have rarefied they could have rarefied	I could have been rarefying you could have been rarefying he could have been rarefying we could have been rarefying you could have been rarefying they could have been rarefying

Negation

Simple form	V-ing form
I couldn't rarefy you couldn't rarefy he couldn't rarefy we couldn't rarefy you couldn't rarefy they couldn't rarefy	I couldn't be rarefying you couldn't be rarefying he couldn't be rarefying we couldn't be rarefying you couldn't be rarefying they couldn't be rarefying
Perfect	V-ing perfect
I couldn't have rarefied you couldn't have rarefied he couldn't have rarefied we couldn't have rarefied you couldn't have rarefied they couldn't have rarefied	I couldn't have been rarefying you couldn't have been rarefying he couldn't have been rarefying we couldn't have been rarefying you couldn't have been rarefying they couldn't have been rarefying

Interrogative form

Simple form	V-ing form
could I rarefy? could you rarefy? could he rarefy? could we rarefy? could you rarefy? could they rarefy?	could I be rarefying? could you be rarefying? could he be rarefying? could we be rarefying? could you be rarefying? could they be rarefying?
Perfect	V-ing perfect
could I have rarefied? could you have rarefied? could he have rarefied? could we have rarefied? could you have rarefied? could they have rarefied?	could I have been rarefying? could you have been rarefying? could he have been rarefying? could we have been rarefying? could you have been rarefying? could they have been rarefying?

Interro-negative form

Simple form	V-ing form
couldn't I rarefy? couldn't you rarefy? couldn't he rarefy? couldn't we rarefy? couldn't you rarefy? couldn't they rarefy?	couldn't I be rarefying? couldn't you be rarefying? couldn't he be rarefying? couldn't we be rarefying? couldn't you be rarefying? couldn't they be rarefying?
Perfect	V-ing perfect
couldn't I have rarefied? couldn't you have rarefied? couldn't he have rarefied? couldn't we have rarefied? couldn't you have rarefied? couldn't they have rarefied?	couldn't I have been rarefying? couldn't you have been rarefying? couldn't he have been rarefying? couldn't we have been rarefying? couldn't you have been rarefying? couldn't they have been rarefying?