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