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