I could de-ice you could de-ice she could de-ice we could de-ice you could de-ice they could de-ice
V-ing form
I could be de-icing you could be de-icing she could be de-icing we could be de-icing you could be de-icing they could be de-icing
Perfect
I could have de-iced you could have de-iced she could have de-iced we could have de-iced you could have de-iced they could have de-iced
V-ing perfect
I could have been de-icing you could have been de-icing she could have been de-icing we could have been de-icing you could have been de-icing they could have been de-icing
Negation
Simple form
I could not de-ice you could not de-ice she could not de-ice we could not de-ice you could not de-ice they could not de-ice
V-ing form
I could not be de-icing you could not be de-icing she could not be de-icing we could not be de-icing you could not be de-icing they could not be de-icing
Perfect
I could not have de-iced you could not have de-iced she could not have de-iced we could not have de-iced you could not have de-iced they could not have de-iced
V-ing perfect
I could not have been de-icing you could not have been de-icing she could not have been de-icing we could not have been de-icing you could not have been de-icing they could not have been de-icing
Interrogative form
Simple form
could I de-ice? could you de-ice? could she de-ice? could we de-ice? could you de-ice? could they de-ice?
V-ing form
could I be de-icing? could you be de-icing? could she be de-icing? could we be de-icing? could you be de-icing? could they be de-icing?
Perfect
could I have de-iced? could you have de-iced? could she have de-iced? could we have de-iced? could you have de-iced? could they have de-iced?
V-ing perfect
could I have been de-icing? could you have been de-icing? could she have been de-icing? could we have been de-icing? could you have been de-icing? could they have been de-icing?
Interro-negative form
Simple form
could I not de-ice? could you not de-ice? could she not de-ice? could we not de-ice? could you not de-ice? could they not de-ice?
V-ing form
could I not be de-icing? could you not be de-icing? could she not be de-icing? could we not be de-icing? could you not be de-icing? could they not be de-icing?
Perfect
could I not have de-iced? could you not have de-iced? could she not have de-iced? could we not have de-iced? could you not have de-iced? could they not have de-iced?
V-ing perfect
could I not have been de-icing? could you not have been de-icing? could she not have been de-icing? could we not have been de-icing? could you not have been de-icing? could they not have been de-icing?