I could float you could float he could float we could float you could float they could float
V-ing form
I could be floating you could be floating he could be floating we could be floating you could be floating they could be floating
Perfect
I could have floated you could have floated he could have floated we could have floated you could have floated they could have floated
V-ing perfect
I could have been floating you could have been floating he could have been floating we could have been floating you could have been floating they could have been floating
Negation
Simple form
I could not float you could not float he could not float we could not float you could not float they could not float
V-ing form
I could not be floating you could not be floating he could not be floating we could not be floating you could not be floating they could not be floating
Perfect
I could not have floated you could not have floated he could not have floated we could not have floated you could not have floated they could not have floated
V-ing perfect
I could not have been floating you could not have been floating he could not have been floating we could not have been floating you could not have been floating they could not have been floating
Interrogative form
Simple form
could I float? could you float? could he float? could we float? could you float? could they float?
V-ing form
could I be floating? could you be floating? could he be floating? could we be floating? could you be floating? could they be floating?
Perfect
could I have floated? could you have floated? could he have floated? could we have floated? could you have floated? could they have floated?
V-ing perfect
could I have been floating? could you have been floating? could he have been floating? could we have been floating? could you have been floating? could they have been floating?
Interro-negative form
Simple form
could I not float? could you not float? could he not float? could we not float? could you not float? could they not float?
V-ing form
could I not be floating? could you not be floating? could he not be floating? could we not be floating? could you not be floating? could they not be floating?
Perfect
could I not have floated? could you not have floated? could he not have floated? could we not have floated? could you not have floated? could they not have floated?
V-ing perfect
could I not have been floating? could you not have been floating? could he not have been floating? could we not have been floating? could you not have been floating? could they not have been floating?