In this task, we ask you to rewrite a sentence in simple English without changing its general meaning. Essentially, you want to make the sentence easier to read by using simpler words, utilizing more straightforward sentence structures, and omitting non-essential information etc.

Oxygen saturation ( symbol S ) is a relative measure of the concentration of oxygen that is dissolved or carried in a given medium as a proportion of the maximal concentration that can be dissolved in that medium .
Oxygen saturation or dissolved oxygen ( DO ) is a relative measure of the amount of oxygen that is dissolved in a given medium .

As a philosopher , Ernst Haeckel wrote " Die Weltra ̈ thsel " ( 1895 – 1899 ; in English : " The Riddle of the Universe " , 1901 ) , the genesis for the term " world riddle " ( " Weltra ̈ tsel " ) ; and " Freedom in Science and Teaching " to support teaching evolution .
As a philosopher , Ernst Haeckel wrote " Die Weltra ̈ tsel " ( 1895 – 1899 , " The Riddle of the Universe " , 1901 ) , and " Freedom in Science and Teaching " to support teaching evolution .

Kenneth Smith Harrelson ( born September 4 , 1941 ) , nicknamed " The Hawk " due to his distinctive profile , is an American former professional baseball All-Star first baseman and outfielder , who played in Major League Baseball ( MLB ) .

Kenneth Smith Harrelson ( born September 4 , 1941 ) , nicknamed " The Hawk " , is an American All-Star first baseman and outfielder in Major League Baseball .