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