How to get smaller string from an unlimited string

I am having trouble reading inline from a file and then breaking into single words. Let's say I read "When the night was young" because that was the first line, I can't figure out how to just get the word "When" from the rest of it, I've tried many times, you're running out of ideas. I'm new to unlimited strings in Ada and just Ada in general. Any help is appreciated, small tips or solution to my problem, thanks.

with Ada.Text_IO;                   use Ada.Text_IO;
with Ada.Strings.Unbounded;         use Ada.Strings.Unbounded;
with Ada.Strings.Unbounded.Text_IO; use Ada.Strings.Unbounded.Text_IO;

with AVL; use AVL;

procedure Spellchecker is
   InWord      : Unbounded_String;
   ReadIn      : String (1..20);
   Break       : Character := ' ';
   RevisedWord : String(1..20);
   Dictionary  : File_Type;
   Paragraph   : File_Type;
   Count       : Integer;
   LastChar    : Integer;
   NewTree     : Tree;

   type Spell is array (Integer range 1..20) of Character;
   Revision : Spell;

begin
   Ada.Text_IO.Open (File => Dictionary,
                     Mode => In_File,
                     Name => "dictionary.txt");
   loop
      exit when End_of_File (File => Dictionary);
      InWord := Get_Line (File => Dictionary);
      Insert (InWord, NewTree);
   end loop;
   Close (File => Dictionary);
   Print (NewTree);
   InWord := Get_Line (File => Paragraph);
   Count := 1;
   Put (InWord);
end Spellchecker;