Readers will have little trouble keeping track of them.

[Eshaan]

Readers will have little trouble keeping track of them.

Is keeping a gerund in the sentence?

Can it be possible to say this "Readers will have little trouble to keep track of them"?

 

[jutfrank]

Is keeping a gerund in the sentence?

It doesn't matter.

Can it be possible to say this "Readers will have little trouble to keep track of them"?

No, you must use the -ing form. Don't worry about the technical terminology.

have trouble doing something
have trouble to do something

 

[Barque]

Is keeping a gerund in the sentence?

No. Not in that sentence, the way it is.