English verb conjugation
COULD OVERWINTER

Regular verb: overwinter - overwintered - overwintered

Affirmation

Simple form	V-ing form
I could overwinter you could overwinter he could overwinter we could overwinter you could overwinter they could overwinter	I could be overwintering you could be overwintering he could be overwintering we could be overwintering you could be overwintering they could be overwintering
Perfect	V-ing perfect
I could have overwintered you could have overwintered he could have overwintered we could have overwintered you could have overwintered they could have overwintered	I could have been overwintering you could have been overwintering he could have been overwintering we could have been overwintering you could have been overwintering they could have been overwintering

Negation

Simple form	V-ing form
I could not overwinter you could not overwinter he could not overwinter we could not overwinter you could not overwinter they could not overwinter	I could not be overwintering you could not be overwintering he could not be overwintering we could not be overwintering you could not be overwintering they could not be overwintering
Perfect	V-ing perfect
I could not have overwintered you could not have overwintered he could not have overwintered we could not have overwintered you could not have overwintered they could not have overwintered	I could not have been overwintering you could not have been overwintering he could not have been overwintering we could not have been overwintering you could not have been overwintering they could not have been overwintering

Interrogative form

Simple form	V-ing form
could I overwinter? could you overwinter? could he overwinter? could we overwinter? could you overwinter? could they overwinter?	could I be overwintering? could you be overwintering? could he be overwintering? could we be overwintering? could you be overwintering? could they be overwintering?
Perfect	V-ing perfect
could I have overwintered? could you have overwintered? could he have overwintered? could we have overwintered? could you have overwintered? could they have overwintered?	could I have been overwintering? could you have been overwintering? could he have been overwintering? could we have been overwintering? could you have been overwintering? could they have been overwintering?

Interro-negative form

Simple form	V-ing form
could I not overwinter? could you not overwinter? could he not overwinter? could we not overwinter? could you not overwinter? could they not overwinter?	could I not be overwintering? could you not be overwintering? could he not be overwintering? could we not be overwintering? could you not be overwintering? could they not be overwintering?
Perfect	V-ing perfect
could I not have overwintered? could you not have overwintered? could he not have overwintered? could we not have overwintered? could you not have overwintered? could they not have overwintered?	could I not have been overwintering? could you not have been overwintering? could he not have been overwintering? could we not have been overwintering? could you not have been overwintering? could they not have been overwintering?