English verb conjugation
COULD RIVET

Regular verb: rivet - riveted - riveted

Affirmation

Simple form	V-ing form
I could rivet you could rivet he could rivet we could rivet you could rivet they could rivet	I could be riveting you could be riveting he could be riveting we could be riveting you could be riveting they could be riveting
Perfect	V-ing perfect
I could have riveted you could have riveted he could have riveted we could have riveted you could have riveted they could have riveted	I could have been riveting you could have been riveting he could have been riveting we could have been riveting you could have been riveting they could have been riveting

Negation

Simple form	V-ing form
I could not rivet you could not rivet he could not rivet we could not rivet you could not rivet they could not rivet	I could not be riveting you could not be riveting he could not be riveting we could not be riveting you could not be riveting they could not be riveting
Perfect	V-ing perfect
I could not have riveted you could not have riveted he could not have riveted we could not have riveted you could not have riveted they could not have riveted	I could not have been riveting you could not have been riveting he could not have been riveting we could not have been riveting you could not have been riveting they could not have been riveting

Interrogative form

Simple form	V-ing form
could I rivet? could you rivet? could he rivet? could we rivet? could you rivet? could they rivet?	could I be riveting? could you be riveting? could he be riveting? could we be riveting? could you be riveting? could they be riveting?
Perfect	V-ing perfect
could I have riveted? could you have riveted? could he have riveted? could we have riveted? could you have riveted? could they have riveted?	could I have been riveting? could you have been riveting? could he have been riveting? could we have been riveting? could you have been riveting? could they have been riveting?

Interro-negative form

Simple form	V-ing form
could I not rivet? could you not rivet? could he not rivet? could we not rivet? could you not rivet? could they not rivet?	could I not be riveting? could you not be riveting? could he not be riveting? could we not be riveting? could you not be riveting? could they not be riveting?
Perfect	V-ing perfect
could I not have riveted? could you not have riveted? could he not have riveted? could we not have riveted? could you not have riveted? could they not have riveted?	could I not have been riveting? could you not have been riveting? could he not have been riveting? could we not have been riveting? could you not have been riveting? could they not have been riveting?