English verb conjugation
COULD ALERT

Regular verb: alert - alerted - alerted

Affirmation

Simple form	V-ing form
I could alert you could alert he could alert we could alert you could alert they could alert	I could be alerting you could be alerting he could be alerting we could be alerting you could be alerting they could be alerting
Perfect	V-ing perfect
I could have alerted you could have alerted he could have alerted we could have alerted you could have alerted they could have alerted	I could have been alerting you could have been alerting he could have been alerting we could have been alerting you could have been alerting they could have been alerting

Negation

Simple form	V-ing form
I could not alert you could not alert he could not alert we could not alert you could not alert they could not alert	I could not be alerting you could not be alerting he could not be alerting we could not be alerting you could not be alerting they could not be alerting
Perfect	V-ing perfect
I could not have alerted you could not have alerted he could not have alerted we could not have alerted you could not have alerted they could not have alerted	I could not have been alerting you could not have been alerting he could not have been alerting we could not have been alerting you could not have been alerting they could not have been alerting

Interrogative form

Simple form	V-ing form
could I alert? could you alert? could he alert? could we alert? could you alert? could they alert?	could I be alerting? could you be alerting? could he be alerting? could we be alerting? could you be alerting? could they be alerting?
Perfect	V-ing perfect
could I have alerted? could you have alerted? could he have alerted? could we have alerted? could you have alerted? could they have alerted?	could I have been alerting? could you have been alerting? could he have been alerting? could we have been alerting? could you have been alerting? could they have been alerting?

Interro-negative form

Simple form	V-ing form
could I not alert? could you not alert? could he not alert? could we not alert? could you not alert? could they not alert?	could I not be alerting? could you not be alerting? could he not be alerting? could we not be alerting? could you not be alerting? could they not be alerting?
Perfect	V-ing perfect
could I not have alerted? could you not have alerted? could he not have alerted? could we not have alerted? could you not have alerted? could they not have alerted?	could I not have been alerting? could you not have been alerting? could he not have been alerting? could we not have been alerting? could you not have been alerting? could they not have been alerting?