Hi, Alexander!  Recently you wrote in a message to All:   
      
   ak>  As it is known, "fuel" is an uncountable noun. But is   
   ak>  it true after "such"? Is it an error to write like this?   
   ak>  My tongue puts "a" involuntary. ;)   
      
   ak>  Uraninum is such a fuel that it causes more problems   
   ak>  than benefits.   
      
      
               And my tongue agrees with yours there....  ;-)   
      
               In general the noun "fuel" is a classification involving anything   
   which when burned provides heat, light, and/or other forms of energy.  In the   
   Christmas carol GOOD KING WENCESLAS the king notices "a poor man... gathering   
   winter fuel".  One might imagine him with an armload of sticks because that's   
   how such people are often represented by illustrators of stories etc.  But it   
   seems to me... having been sent as a child to gather kindling in the woods...   
   that dried moss & leaves & pine cones also qualify as "fuel" in this context.   
      
               FOWLER'S alludes to idiomatic uses of "such" and offers examples,   
   but makes no attempt to explain them.  Idioms defy explanation... but maybe I   
   can shed a bit more light on the use of the word "fuel" than the average desk   
   dictionary evidently does.  This rather broad category includes various items   
   which are countable although others may not be.  Dried leaves are a (type of)   
   fuel... wood is a (type of) fuel... oil is a (type of) fuel.  When folks grow   
   weary of reiterating the same words & tend to decide in favour of leaving out   
   the parenthesized bit, that's quite understandable AFAIC.  Native speakers of   
   English have been dropping inflections for a thousand years.  With the Norman   
   invasion of an island which had already been invaded umpteen times, they felt   
   they had two choices... either head for the hills or learn that when somebody   
   wants "beef" and you have "cattle" it may be worth your while to stay put.  I   
   sometimes wish those who try to make improvements on my native language had a   
   better grasp of the big picture, but if they describe xxx as "a fuel" I won't   
   quibble because they've left the essential meaning of the words intact.  :-))   
      
      
      
      
   --- timEd/386 1.10.y2k+   
    * Origin: Wits' End, Vancouver CANADA (1:153/716)