English verb conjugation
COULD TWITTER

Regular verb: twitter - twittered - twittered

Affirmation

Simple form	V-ing form
I could twitter you could twitter he could twitter we could twitter you could twitter they could twitter	I could be twittering you could be twittering he could be twittering we could be twittering you could be twittering they could be twittering
Perfect	V-ing perfect
I could have twittered you could have twittered he could have twittered we could have twittered you could have twittered they could have twittered	I could have been twittering you could have been twittering he could have been twittering we could have been twittering you could have been twittering they could have been twittering

Negation

Simple form	V-ing form
I could not twitter you could not twitter he could not twitter we could not twitter you could not twitter they could not twitter	I could not be twittering you could not be twittering he could not be twittering we could not be twittering you could not be twittering they could not be twittering
Perfect	V-ing perfect
I could not have twittered you could not have twittered he could not have twittered we could not have twittered you could not have twittered they could not have twittered	I could not have been twittering you could not have been twittering he could not have been twittering we could not have been twittering you could not have been twittering they could not have been twittering

Interrogative form

Simple form	V-ing form
could I twitter? could you twitter? could he twitter? could we twitter? could you twitter? could they twitter?	could I be twittering? could you be twittering? could he be twittering? could we be twittering? could you be twittering? could they be twittering?
Perfect	V-ing perfect
could I have twittered? could you have twittered? could he have twittered? could we have twittered? could you have twittered? could they have twittered?	could I have been twittering? could you have been twittering? could he have been twittering? could we have been twittering? could you have been twittering? could they have been twittering?

Interro-negative form

Simple form	V-ing form
could I not twitter? could you not twitter? could he not twitter? could we not twitter? could you not twitter? could they not twitter?	could I not be twittering? could you not be twittering? could he not be twittering? could we not be twittering? could you not be twittering? could they not be twittering?
Perfect	V-ing perfect
could I not have twittered? could you not have twittered? could he not have twittered? could we not have twittered? could you not have twittered? could they not have twittered?	could I not have been twittering? could you not have been twittering? could he not have been twittering? could we not have been twittering? could you not have been twittering? could they not have been twittering?