English verb conjugation
COULD GRATULATE

Regular verb: gratulate - gratulated - gratulated

Affirmation

Simple form	V-ing form
I could gratulate you could gratulate he could gratulate we could gratulate you could gratulate they could gratulate	I could be gratulating you could be gratulating he could be gratulating we could be gratulating you could be gratulating they could be gratulating
Perfect	V-ing perfect
I could have gratulated you could have gratulated he could have gratulated we could have gratulated you could have gratulated they could have gratulated	I could have been gratulating you could have been gratulating he could have been gratulating we could have been gratulating you could have been gratulating they could have been gratulating

Negation

Simple form	V-ing form
I could not gratulate you could not gratulate he could not gratulate we could not gratulate you could not gratulate they could not gratulate	I could not be gratulating you could not be gratulating he could not be gratulating we could not be gratulating you could not be gratulating they could not be gratulating
Perfect	V-ing perfect
I could not have gratulated you could not have gratulated he could not have gratulated we could not have gratulated you could not have gratulated they could not have gratulated	I could not have been gratulating you could not have been gratulating he could not have been gratulating we could not have been gratulating you could not have been gratulating they could not have been gratulating

Interrogative form

Simple form	V-ing form
could I gratulate? could you gratulate? could he gratulate? could we gratulate? could you gratulate? could they gratulate?	could I be gratulating? could you be gratulating? could he be gratulating? could we be gratulating? could you be gratulating? could they be gratulating?
Perfect	V-ing perfect
could I have gratulated? could you have gratulated? could he have gratulated? could we have gratulated? could you have gratulated? could they have gratulated?	could I have been gratulating? could you have been gratulating? could he have been gratulating? could we have been gratulating? could you have been gratulating? could they have been gratulating?

Interro-negative form

Simple form	V-ing form
could I not gratulate? could you not gratulate? could he not gratulate? could we not gratulate? could you not gratulate? could they not gratulate?	could I not be gratulating? could you not be gratulating? could he not be gratulating? could we not be gratulating? could you not be gratulating? could they not be gratulating?
Perfect	V-ing perfect
could I not have gratulated? could you not have gratulated? could he not have gratulated? could we not have gratulated? could you not have gratulated? could they not have gratulated?	could I not have been gratulating? could you not have been gratulating? could he not have been gratulating? could we not have been gratulating? could you not have been gratulating? could they not have been gratulating?