Awk: generate random sentences

cat /usr/share/dict/words | 
  grep -v "'" | 
  shuf | 
  awk -v wordCount=100 -v wordsPerSentence=5 '
    BEGIN {i=0} 
    (NR<wordCount) {
      if (i<wordsPerSentence) {
        a[i]=$0; 
        i++
      } else {
        for (j=0;j<length(a);j++) {
          printf ("%s ",a[j])
      }
      print
      i=0
    }
  }'