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