$ FAKE=$PREFfeit
$ echo $WAX $FAKE

$

     .    .  
,   PREFclockwise  PREFfeit    , -
    .       
     .    ,   PREF 
    :

$ PREF=counter
$ WAY=$(PREF)clockwise
$ FAKE=${PREF)feit
$ echo $WAY $FAKE

counterclockwise counterfeit

$(...)  

  (.  "$(...)  '...'   "  
 )        -
. (     ,    ,  
  .)        ,
      .  -
   

$()

        
.     ,    -
   .

  

    ,  -
 ,      .  -
   :

$[]

       
 ;       .
 bash   ,    ,   -
 ,      
 .

       
 ,    ,    -
  letter, txt.        -
  ;       -
  :

$ echo $[$(wc -I letter, txt | cut -cl-7)/66 + 1]

6

340  III.   Red Hat Linux