I could ankylose you could ankylose he could ankylose we could ankylose you could ankylose they could ankylose
V-ing form
I could be ankylosing you could be ankylosing he could be ankylosing we could be ankylosing you could be ankylosing they could be ankylosing
Perfect
I could have ankylosed you could have ankylosed he could have ankylosed we could have ankylosed you could have ankylosed they could have ankylosed
V-ing perfect
I could have been ankylosing you could have been ankylosing he could have been ankylosing we could have been ankylosing you could have been ankylosing they could have been ankylosing
Negation
Simple form
I couldn't ankylose you couldn't ankylose he couldn't ankylose we couldn't ankylose you couldn't ankylose they couldn't ankylose
V-ing form
I couldn't be ankylosing you couldn't be ankylosing he couldn't be ankylosing we couldn't be ankylosing you couldn't be ankylosing they couldn't be ankylosing
Perfect
I couldn't have ankylosed you couldn't have ankylosed he couldn't have ankylosed we couldn't have ankylosed you couldn't have ankylosed they couldn't have ankylosed
V-ing perfect
I couldn't have been ankylosing you couldn't have been ankylosing he couldn't have been ankylosing we couldn't have been ankylosing you couldn't have been ankylosing they couldn't have been ankylosing
Interrogative form
Simple form
could I ankylose? could you ankylose? could he ankylose? could we ankylose? could you ankylose? could they ankylose?
V-ing form
could I be ankylosing? could you be ankylosing? could he be ankylosing? could we be ankylosing? could you be ankylosing? could they be ankylosing?
Perfect
could I have ankylosed? could you have ankylosed? could he have ankylosed? could we have ankylosed? could you have ankylosed? could they have ankylosed?
V-ing perfect
could I have been ankylosing? could you have been ankylosing? could he have been ankylosing? could we have been ankylosing? could you have been ankylosing? could they have been ankylosing?
Interro-negative form
Simple form
couldn't I ankylose? couldn't you ankylose? couldn't he ankylose? couldn't we ankylose? couldn't you ankylose? couldn't they ankylose?
V-ing form
couldn't I be ankylosing? couldn't you be ankylosing? couldn't he be ankylosing? couldn't we be ankylosing? couldn't you be ankylosing? couldn't they be ankylosing?
Perfect
couldn't I have ankylosed? couldn't you have ankylosed? couldn't he have ankylosed? couldn't we have ankylosed? couldn't you have ankylosed? couldn't they have ankylosed?
V-ing perfect
couldn't I have been ankylosing? couldn't you have been ankylosing? couldn't he have been ankylosing? couldn't we have been ankylosing? couldn't you have been ankylosing? couldn't they have been ankylosing?