I could chain you could chain he could chain we could chain you could chain they could chain
V-ing form
I could be chaining you could be chaining he could be chaining we could be chaining you could be chaining they could be chaining
Perfect
I could have chained you could have chained he could have chained we could have chained you could have chained they could have chained
V-ing perfect
I could have been chaining you could have been chaining he could have been chaining we could have been chaining you could have been chaining they could have been chaining
Negation
Simple form
I could not chain you could not chain he could not chain we could not chain you could not chain they could not chain
V-ing form
I could not be chaining you could not be chaining he could not be chaining we could not be chaining you could not be chaining they could not be chaining
Perfect
I could not have chained you could not have chained he could not have chained we could not have chained you could not have chained they could not have chained
V-ing perfect
I could not have been chaining you could not have been chaining he could not have been chaining we could not have been chaining you could not have been chaining they could not have been chaining
Interrogative form
Simple form
could I chain? could you chain? could he chain? could we chain? could you chain? could they chain?
V-ing form
could I be chaining? could you be chaining? could he be chaining? could we be chaining? could you be chaining? could they be chaining?
Perfect
could I have chained? could you have chained? could he have chained? could we have chained? could you have chained? could they have chained?
V-ing perfect
could I have been chaining? could you have been chaining? could he have been chaining? could we have been chaining? could you have been chaining? could they have been chaining?
Interro-negative form
Simple form
could I not chain? could you not chain? could he not chain? could we not chain? could you not chain? could they not chain?
V-ing form
could I not be chaining? could you not be chaining? could he not be chaining? could we not be chaining? could you not be chaining? could they not be chaining?
Perfect
could I not have chained? could you not have chained? could he not have chained? could we not have chained? could you not have chained? could they not have chained?
V-ing perfect
could I not have been chaining? could you not have been chaining? could he not have been chaining? could we not have been chaining? could you not have been chaining? could they not have been chaining?