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