title: In Vim, how would I replace the only the first occurrence of a certain word in each line with another word?
body: <p><strong><em>For instance, if I had:</em></strong></p>
  
  <p>eat eat eat eat cake cake</p>
  
  <p>eat eat eat cake</p>
  
  <p>cake eat eat cake</p>
  
  <p><strong>How would I only the first instance of cake in each line with pear?</strong></p>
  
  <p>eat eat eat eat pear cake</p>
  
  <p>eat eat eat pear</p>
  
  <p>pear eat eat cake</p>