Filters determine what is displayed on the screen and is visible to the learner.
TeXT Handler uses a lexical scanner for English that allows filtering to be automated. TeXT Handler is capable of recognizing a number of grammatical words and distribute them into different grammatical categories. Punctuation marks, numeric values are also detected.
Filtering can be automatic or interactive.
Another option allows filters to operate, once the frequency set, every third, fourth ... word.
Custom filtering is also possible thanks to a special format.
Built-in filters bind TeXT Handler to English. Building other filters for other languages may be envisioned ( see scanner ).