I could party you could party she could party we could party you could party they could party
V-ing form
I could be partying you could be partying she could be partying we could be partying you could be partying they could be partying
Perfect
I could have partied you could have partied she could have partied we could have partied you could have partied they could have partied
V-ing perfect
I could have been partying you could have been partying she could have been partying we could have been partying you could have been partying they could have been partying
Negation
Simple form
I couldn't party you couldn't party she couldn't party we couldn't party you couldn't party they couldn't party
V-ing form
I couldn't be partying you couldn't be partying she couldn't be partying we couldn't be partying you couldn't be partying they couldn't be partying
Perfect
I couldn't have partied you couldn't have partied she couldn't have partied we couldn't have partied you couldn't have partied they couldn't have partied
V-ing perfect
I couldn't have been partying you couldn't have been partying she couldn't have been partying we couldn't have been partying you couldn't have been partying they couldn't have been partying
Interrogative form
Simple form
could I party? could you party? could she party? could we party? could you party? could they party?
V-ing form
could I be partying? could you be partying? could she be partying? could we be partying? could you be partying? could they be partying?
Perfect
could I have partied? could you have partied? could she have partied? could we have partied? could you have partied? could they have partied?
V-ing perfect
could I have been partying? could you have been partying? could she have been partying? could we have been partying? could you have been partying? could they have been partying?
Interro-negative form
Simple form
couldn't I party? couldn't you party? couldn't she party? couldn't we party? couldn't you party? couldn't they party?
V-ing form
couldn't I be partying? couldn't you be partying? couldn't she be partying? couldn't we be partying? couldn't you be partying? couldn't they be partying?
Perfect
couldn't I have partied? couldn't you have partied? couldn't she have partied? couldn't we have partied? couldn't you have partied? couldn't they have partied?
V-ing perfect
couldn't I have been partying? couldn't you have been partying? couldn't she have been partying? couldn't we have been partying? couldn't you have been partying? couldn't they have been partying?