English verb conjugation
CAN INDEX

Regular verb: index - indexed - indexed

Affirmation

Simple form	V-ing form
I can index you can index he can index we can index you can index they can index	I can be indexing you can be indexing he can be indexing we can be indexing you can be indexing they can be indexing
Perfect	V-ing perfect
I can have indexed you can have indexed he can have indexed we can have indexed you can have indexed they can have indexed	I can have been indexing you can have been indexing he can have been indexing we can have been indexing you can have been indexing they can have been indexing

Negation

Simple form	V-ing form
I can't index you can't index he can't index we can't index you can't index they can't index	I can't be indexing you can't be indexing he can't be indexing we can't be indexing you can't be indexing they can't be indexing
Perfect	V-ing perfect
I can't have indexed you can't have indexed he can't have indexed we can't have indexed you can't have indexed they can't have indexed	I can't have been indexing you can't have been indexing he can't have been indexing we can't have been indexing you can't have been indexing they can't have been indexing

Interrogative form

Simple form	V-ing form
can I index? can you index? can he index? can we index? can you index? can they index?	can I be indexing? can you be indexing? can he be indexing? can we be indexing? can you be indexing? can they be indexing?
Perfect	V-ing perfect
can I have indexed? can you have indexed? can he have indexed? can we have indexed? can you have indexed? can they have indexed?	can I have been indexing? can you have been indexing? can he have been indexing? can we have been indexing? can you have been indexing? can they have been indexing?

Interro-negative form

Simple form	V-ing form
can't I index? can't you index? can't he index? can't we index? can't you index? can't they index?	can't I be indexing? can't you be indexing? can't he be indexing? can't we be indexing? can't you be indexing? can't they be indexing?
Perfect	V-ing perfect
can't I have indexed? can't you have indexed? can't he have indexed? can't we have indexed? can't you have indexed? can't they have indexed?	can't I have been indexing? can't you have been indexing? can't he have been indexing? can't we have been indexing? can't you have been indexing? can't they have been indexing?