Due to this inherent ambiguity , manual annotations usually distinguish between sure correspondences for unambiguous translations , and possible , for ambiguous translations ( Och and Ney 2003 ) .
a systematic comparison of various statistical alignment models
Franz Josef Och Hermann Ney
There are many reasons why a simple word-to-word ( 1-to-1 ) correspondence is not possible for every sentence pair : for instance , auxiliary verbs used in one language but not the other ( e.g. , English He walked and French Il est all Â´ e ) , articles required in one language but optional in the other ( e.g. , English Cars use gas and Portuguese Os carros usam gasolina ) , cases where the content is expressed using multiple words in one language and a single word in the other language ( e.g. , agglutination such as English weapons of mass destruction and German Massenvernichtungswaffen ) , and expressions translated indirectly . Due to this inherent ambiguity , manual annotations usually distinguish between sure correspondences for unambiguous translations , and possible , for ambiguous translations ( Och and Ney 2003 ) . The top row of Figure 1 shows two word alignments between an English -- French sentence pair .
Due to this inherent ambiguity , manual annotations usually distinguish between sure correspondences for unambiguous translations , and possible , for ambiguous translations ( @@CITATION ) .