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