Warning, this verb may not exist. Conjugation is given as example.
Affirmation
Simple form
I could gronder passer you could gronder passer he could gronder passer we could gronder passer you could gronder passer they could gronder passer
V-ing form
I could be gronder passering you could be gronder passering he could be gronder passering we could be gronder passering you could be gronder passering they could be gronder passering
Perfect
I could have gronder passered you could have gronder passered he could have gronder passered we could have gronder passered you could have gronder passered they could have gronder passered
V-ing perfect
I could have been gronder passering you could have been gronder passering he could have been gronder passering we could have been gronder passering you could have been gronder passering they could have been gronder passering
Negation
Simple form
I couldn't gronder passer you couldn't gronder passer he couldn't gronder passer we couldn't gronder passer you couldn't gronder passer they couldn't gronder passer
V-ing form
I couldn't be gronder passering you couldn't be gronder passering he couldn't be gronder passering we couldn't be gronder passering you couldn't be gronder passering they couldn't be gronder passering
Perfect
I couldn't have gronder passered you couldn't have gronder passered he couldn't have gronder passered we couldn't have gronder passered you couldn't have gronder passered they couldn't have gronder passered
V-ing perfect
I couldn't have been gronder passering you couldn't have been gronder passering he couldn't have been gronder passering we couldn't have been gronder passering you couldn't have been gronder passering they couldn't have been gronder passering
Interrogative form
Simple form
could I gronder passer? could you gronder passer? could he gronder passer? could we gronder passer? could you gronder passer? could they gronder passer?
V-ing form
could I be gronder passering? could you be gronder passering? could he be gronder passering? could we be gronder passering? could you be gronder passering? could they be gronder passering?
Perfect
could I have gronder passered? could you have gronder passered? could he have gronder passered? could we have gronder passered? could you have gronder passered? could they have gronder passered?
V-ing perfect
could I have been gronder passering? could you have been gronder passering? could he have been gronder passering? could we have been gronder passering? could you have been gronder passering? could they have been gronder passering?
Interro-negative form
Simple form
couldn't I gronder passer? couldn't you gronder passer? couldn't he gronder passer? couldn't we gronder passer? couldn't you gronder passer? couldn't they gronder passer?
V-ing form
couldn't I be gronder passering? couldn't you be gronder passering? couldn't he be gronder passering? couldn't we be gronder passering? couldn't you be gronder passering? couldn't they be gronder passering?
Perfect
couldn't I have gronder passered? couldn't you have gronder passered? couldn't he have gronder passered? couldn't we have gronder passered? couldn't you have gronder passered? couldn't they have gronder passered?
V-ing perfect
couldn't I have been gronder passering? couldn't you have been gronder passering? couldn't he have been gronder passering? couldn't we have been gronder passering? couldn't you have been gronder passering? couldn't they have been gronder passering?