I could federate you could federate he could federate we could federate you could federate they could federate
V-ing form
I could be federating you could be federating he could be federating we could be federating you could be federating they could be federating
Perfect
I could have federated you could have federated he could have federated we could have federated you could have federated they could have federated
V-ing perfect
I could have been federating you could have been federating he could have been federating we could have been federating you could have been federating they could have been federating
Negation
Simple form
I could not federate you could not federate he could not federate we could not federate you could not federate they could not federate
V-ing form
I could not be federating you could not be federating he could not be federating we could not be federating you could not be federating they could not be federating
Perfect
I could not have federated you could not have federated he could not have federated we could not have federated you could not have federated they could not have federated
V-ing perfect
I could not have been federating you could not have been federating he could not have been federating we could not have been federating you could not have been federating they could not have been federating
Interrogative form
Simple form
could I federate? could you federate? could he federate? could we federate? could you federate? could they federate?
V-ing form
could I be federating? could you be federating? could he be federating? could we be federating? could you be federating? could they be federating?
Perfect
could I have federated? could you have federated? could he have federated? could we have federated? could you have federated? could they have federated?
V-ing perfect
could I have been federating? could you have been federating? could he have been federating? could we have been federating? could you have been federating? could they have been federating?
Interro-negative form
Simple form
could I not federate? could you not federate? could he not federate? could we not federate? could you not federate? could they not federate?
V-ing form
could I not be federating? could you not be federating? could he not be federating? could we not be federating? could you not be federating? could they not be federating?
Perfect
could I not have federated? could you not have federated? could he not have federated? could we not have federated? could you not have federated? could they not have federated?
V-ing perfect
could I not have been federating? could you not have been federating? could he not have been federating? could we not have been federating? could you not have been federating? could they not have been federating?