English verb conjugation
COULD COUNTERSINK

Irregular verb: countersink - countersank - countersunk

Affirmation

Simple form	V-ing form
I could countersink you could countersink he could countersink we could countersink you could countersink they could countersink	I could be countersinking you could be countersinking he could be countersinking we could be countersinking you could be countersinking they could be countersinking
Perfect	V-ing perfect
I could have countersunk you could have countersunk he could have countersunk we could have countersunk you could have countersunk they could have countersunk	I could have been countersinking you could have been countersinking he could have been countersinking we could have been countersinking you could have been countersinking they could have been countersinking

Negation

Simple form	V-ing form
I couldn't countersink you couldn't countersink he couldn't countersink we couldn't countersink you couldn't countersink they couldn't countersink	I couldn't be countersinking you couldn't be countersinking he couldn't be countersinking we couldn't be countersinking you couldn't be countersinking they couldn't be countersinking
Perfect	V-ing perfect
I couldn't have countersunk you couldn't have countersunk he couldn't have countersunk we couldn't have countersunk you couldn't have countersunk they couldn't have countersunk	I couldn't have been countersinking you couldn't have been countersinking he couldn't have been countersinking we couldn't have been countersinking you couldn't have been countersinking they couldn't have been countersinking

Interrogative form

Simple form	V-ing form
could I countersink? could you countersink? could he countersink? could we countersink? could you countersink? could they countersink?	could I be countersinking? could you be countersinking? could he be countersinking? could we be countersinking? could you be countersinking? could they be countersinking?
Perfect	V-ing perfect
could I have countersunk? could you have countersunk? could he have countersunk? could we have countersunk? could you have countersunk? could they have countersunk?	could I have been countersinking? could you have been countersinking? could he have been countersinking? could we have been countersinking? could you have been countersinking? could they have been countersinking?

Interro-negative form

Simple form	V-ing form
couldn't I countersink? couldn't you countersink? couldn't he countersink? couldn't we countersink? couldn't you countersink? couldn't they countersink?	couldn't I be countersinking? couldn't you be countersinking? couldn't he be countersinking? couldn't we be countersinking? couldn't you be countersinking? couldn't they be countersinking?
Perfect	V-ing perfect
couldn't I have countersunk? couldn't you have countersunk? couldn't he have countersunk? couldn't we have countersunk? couldn't you have countersunk? couldn't they have countersunk?	couldn't I have been countersinking? couldn't you have been countersinking? couldn't he have been countersinking? couldn't we have been countersinking? couldn't you have been countersinking? couldn't they have been countersinking?