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 couldn't gratulate you couldn't gratulate he couldn't gratulate we couldn't gratulate you couldn't gratulate they couldn't gratulate	I couldn't be gratulating you couldn't be gratulating he couldn't be gratulating we couldn't be gratulating you couldn't be gratulating they couldn't be gratulating
Perfect	V-ing perfect
I couldn't have gratulated you couldn't have gratulated he couldn't have gratulated we couldn't have gratulated you couldn't have gratulated they couldn't have gratulated	I couldn't have been gratulating you couldn't have been gratulating he couldn't have been gratulating we couldn't have been gratulating you couldn't have been gratulating they couldn't 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
couldn't I gratulate? couldn't you gratulate? couldn't he gratulate? couldn't we gratulate? couldn't you gratulate? couldn't they gratulate?	couldn't I be gratulating? couldn't you be gratulating? couldn't he be gratulating? couldn't we be gratulating? couldn't you be gratulating? couldn't they be gratulating?
Perfect	V-ing perfect
couldn't I have gratulated? couldn't you have gratulated? couldn't he have gratulated? couldn't we have gratulated? couldn't you have gratulated? couldn't they have gratulated?	couldn't I have been gratulating? couldn't you have been gratulating? couldn't he have been gratulating? couldn't we have been gratulating? couldn't you have been gratulating? couldn't they have been gratulating?