I could sightsee you could sightsee he could sightsee we could sightsee you could sightsee they could sightsee
Forme en V-ing
I could be sightseeing you could be sightseeing he could be sightseeing we could be sightseeing you could be sightseeing they could be sightseeing
Perfect
I could have sightseed you could have sightseed he could have sightseed we could have sightseed you could have sightseed they could have sightseed
Perfect en V-ing
I could have been sightseeing you could have been sightseeing he could have been sightseeing we could have been sightseeing you could have been sightseeing they could have been sightseeing
Négation
Forme simple
I could not sightsee you could not sightsee he could not sightsee we could not sightsee you could not sightsee they could not sightsee
Forme en V-ing
I could not be sightseeing you could not be sightseeing he could not be sightseeing we could not be sightseeing you could not be sightseeing they could not be sightseeing
Perfect
I could not have sightseed you could not have sightseed he could not have sightseed we could not have sightseed you could not have sightseed they could not have sightseed
Perfect en V-ing
I could not have been sightseeing you could not have been sightseeing he could not have been sightseeing we could not have been sightseeing you could not have been sightseeing they could not have been sightseeing
Forme interrogative
Forme simple
could I sightsee? could you sightsee? could he sightsee? could we sightsee? could you sightsee? could they sightsee?
Forme en V-ing
could I be sightseeing? could you be sightseeing? could he be sightseeing? could we be sightseeing? could you be sightseeing? could they be sightseeing?
Perfect
could I have sightseed? could you have sightseed? could he have sightseed? could we have sightseed? could you have sightseed? could they have sightseed?
Perfect en V-ing
could I have been sightseeing? could you have been sightseeing? could he have been sightseeing? could we have been sightseeing? could you have been sightseeing? could they have been sightseeing?
Forme interro-négative
Forme simple
could I not sightsee? could you not sightsee? could he not sightsee? could we not sightsee? could you not sightsee? could they not sightsee?
Forme en V-ing
could I not be sightseeing? could you not be sightseeing? could he not be sightseeing? could we not be sightseeing? could you not be sightseeing? could they not be sightseeing?
Perfect
could I not have sightseed? could you not have sightseed? could he not have sightseed? could we not have sightseed? could you not have sightseed? could they not have sightseed?
Perfect en V-ing
could I not have been sightseeing? could you not have been sightseeing? could he not have been sightseeing? could we not have been sightseeing? could you not have been sightseeing? could they not have been sightseeing?