I could hollow you could hollow he could hollow we could hollow you could hollow they could hollow
V-ing form
I could be hollowing you could be hollowing he could be hollowing we could be hollowing you could be hollowing they could be hollowing
Perfect
I could have hollowed you could have hollowed he could have hollowed we could have hollowed you could have hollowed they could have hollowed
V-ing perfect
I could have been hollowing you could have been hollowing he could have been hollowing we could have been hollowing you could have been hollowing they could have been hollowing
Negation
Simple form
I could not hollow you could not hollow he could not hollow we could not hollow you could not hollow they could not hollow
V-ing form
I could not be hollowing you could not be hollowing he could not be hollowing we could not be hollowing you could not be hollowing they could not be hollowing
Perfect
I could not have hollowed you could not have hollowed he could not have hollowed we could not have hollowed you could not have hollowed they could not have hollowed
V-ing perfect
I could not have been hollowing you could not have been hollowing he could not have been hollowing we could not have been hollowing you could not have been hollowing they could not have been hollowing
Interrogative form
Simple form
could I hollow? could you hollow? could he hollow? could we hollow? could you hollow? could they hollow?
V-ing form
could I be hollowing? could you be hollowing? could he be hollowing? could we be hollowing? could you be hollowing? could they be hollowing?
Perfect
could I have hollowed? could you have hollowed? could he have hollowed? could we have hollowed? could you have hollowed? could they have hollowed?
V-ing perfect
could I have been hollowing? could you have been hollowing? could he have been hollowing? could we have been hollowing? could you have been hollowing? could they have been hollowing?
Interro-negative form
Simple form
could I not hollow? could you not hollow? could he not hollow? could we not hollow? could you not hollow? could they not hollow?
V-ing form
could I not be hollowing? could you not be hollowing? could he not be hollowing? could we not be hollowing? could you not be hollowing? could they not be hollowing?
Perfect
could I not have hollowed? could you not have hollowed? could he not have hollowed? could we not have hollowed? could you not have hollowed? could they not have hollowed?
V-ing perfect
could I not have been hollowing? could you not have been hollowing? could he not have been hollowing? could we not have been hollowing? could you not have been hollowing? could they not have been hollowing?