I could thumbtack you could thumbtack he could thumbtack we could thumbtack you could thumbtack they could thumbtack
Forme en V-ing
I could be thumbtacking you could be thumbtacking he could be thumbtacking we could be thumbtacking you could be thumbtacking they could be thumbtacking
Perfect
I could have thumbtacked you could have thumbtacked he could have thumbtacked we could have thumbtacked you could have thumbtacked they could have thumbtacked
Perfect en V-ing
I could have been thumbtacking you could have been thumbtacking he could have been thumbtacking we could have been thumbtacking you could have been thumbtacking they could have been thumbtacking
Négation
Forme simple
I couldn't thumbtack you couldn't thumbtack he couldn't thumbtack we couldn't thumbtack you couldn't thumbtack they couldn't thumbtack
Forme en V-ing
I couldn't be thumbtacking you couldn't be thumbtacking he couldn't be thumbtacking we couldn't be thumbtacking you couldn't be thumbtacking they couldn't be thumbtacking
Perfect
I couldn't have thumbtacked you couldn't have thumbtacked he couldn't have thumbtacked we couldn't have thumbtacked you couldn't have thumbtacked they couldn't have thumbtacked
Perfect en V-ing
I couldn't have been thumbtacking you couldn't have been thumbtacking he couldn't have been thumbtacking we couldn't have been thumbtacking you couldn't have been thumbtacking they couldn't have been thumbtacking
Forme interrogative
Forme simple
could I thumbtack? could you thumbtack? could he thumbtack? could we thumbtack? could you thumbtack? could they thumbtack?
Forme en V-ing
could I be thumbtacking? could you be thumbtacking? could he be thumbtacking? could we be thumbtacking? could you be thumbtacking? could they be thumbtacking?
Perfect
could I have thumbtacked? could you have thumbtacked? could he have thumbtacked? could we have thumbtacked? could you have thumbtacked? could they have thumbtacked?
Perfect en V-ing
could I have been thumbtacking? could you have been thumbtacking? could he have been thumbtacking? could we have been thumbtacking? could you have been thumbtacking? could they have been thumbtacking?
Forme interro-négative
Forme simple
couldn't I thumbtack? couldn't you thumbtack? couldn't he thumbtack? couldn't we thumbtack? couldn't you thumbtack? couldn't they thumbtack?
Forme en V-ing
couldn't I be thumbtacking? couldn't you be thumbtacking? couldn't he be thumbtacking? couldn't we be thumbtacking? couldn't you be thumbtacking? couldn't they be thumbtacking?
Perfect
couldn't I have thumbtacked? couldn't you have thumbtacked? couldn't he have thumbtacked? couldn't we have thumbtacked? couldn't you have thumbtacked? couldn't they have thumbtacked?
Perfect en V-ing
couldn't I have been thumbtacking? couldn't you have been thumbtacking? couldn't he have been thumbtacking? couldn't we have been thumbtacking? couldn't you have been thumbtacking? couldn't they have been thumbtacking?