Help System (web edition)

F2 J:
   initiates a search for an incomplete word just before the cursor
   and completes it by the first matching word found in the current
   edit field.
   Example: Assume that the user has written...
      Ouagadougou is the capital of Burkina Faso.
      The population of Ou_
   By pressing PREFIX J the system will complete the word as
      The population of Ouagadougou 
   and the user can continue typing.
F1 J:
   works as F2 J but makes possible to search for phrases starting by
   two or more words typed as first words on the edit line.