English verb conjugation
COULD UNBOX

Regular verb: unbox - unboxed - unboxed

Affirmation

Simple form	V-ing form
I could unbox you could unbox he could unbox we could unbox you could unbox they could unbox	I could be unboxing you could be unboxing he could be unboxing we could be unboxing you could be unboxing they could be unboxing
Perfect	V-ing perfect
I could have unboxed you could have unboxed he could have unboxed we could have unboxed you could have unboxed they could have unboxed	I could have been unboxing you could have been unboxing he could have been unboxing we could have been unboxing you could have been unboxing they could have been unboxing

Negation

Simple form	V-ing form
I could not unbox you could not unbox he could not unbox we could not unbox you could not unbox they could not unbox	I could not be unboxing you could not be unboxing he could not be unboxing we could not be unboxing you could not be unboxing they could not be unboxing
Perfect	V-ing perfect
I could not have unboxed you could not have unboxed he could not have unboxed we could not have unboxed you could not have unboxed they could not have unboxed	I could not have been unboxing you could not have been unboxing he could not have been unboxing we could not have been unboxing you could not have been unboxing they could not have been unboxing

Interrogative form

Simple form	V-ing form
could I unbox? could you unbox? could he unbox? could we unbox? could you unbox? could they unbox?	could I be unboxing? could you be unboxing? could he be unboxing? could we be unboxing? could you be unboxing? could they be unboxing?
Perfect	V-ing perfect
could I have unboxed? could you have unboxed? could he have unboxed? could we have unboxed? could you have unboxed? could they have unboxed?	could I have been unboxing? could you have been unboxing? could he have been unboxing? could we have been unboxing? could you have been unboxing? could they have been unboxing?

Interro-negative form

Simple form	V-ing form
could I not unbox? could you not unbox? could he not unbox? could we not unbox? could you not unbox? could they not unbox?	could I not be unboxing? could you not be unboxing? could he not be unboxing? could we not be unboxing? could you not be unboxing? could they not be unboxing?
Perfect	V-ing perfect
could I not have unboxed? could you not have unboxed? could he not have unboxed? could we not have unboxed? could you not have unboxed? could they not have unboxed?	could I not have been unboxing? could you not have been unboxing? could he not have been unboxing? could we not have been unboxing? could you not have been unboxing? could they not have been unboxing?