title: Extracting synonymous terms from wordnet using synonym()
body: <p>Supposed I am pulling the synonyms of "help" by the function of synonyms() from wordnet and get the followings: </p>
  
  <pre><code>Str = synonyms("help")    
  Str
  [1] "c(\"aid\", \"assist\", \"assistance\", \"help\")"     
  [2] "c(\"aid\", \"assistance\", \"help\")"                 
  [3] "c(\"assistant\", \"helper\", \"help\", \"supporter\")"
  [4] "c(\"avail\", \"help\", \"service\")"  
  </code></pre>
  
  <p>Then I can get a one character string using </p>
  
  <pre><code>unique(unlist(lapply(parse(text=Str),eval)))
  </code></pre>
  
  <p>at the end that looks like this: </p>
  
  <pre><code>[1] "aid"        "assist"     "assistance" "help"       "assistant"  "helper"     "supporter" 
  [8] "avail"      "service"
  </code></pre>
  
  <p>The above process was suggested by Gabor Grothendieck. His/Her solution is good, but I still couldn't figure out that if I change the query term into "company", "boy", or someone else, an error message will be responsed.</p>
  
  <p>One possible reason maybe due to the "sixth" synonym of "company" (please see below) is a single term and does not follow the format of "c(\"company\")". </p>
  
  <pre><code>synonyms("company")
  
  [1] "c(\"caller\", \"company\")"                                    
  [2] "c(\"company\", \"companionship\", \"fellowship\", \"society\")"
  [3] "c(\"company\", \"troupe\")"                                    
  [4] "c(\"party\", \"company\")"                                     
  [5] "c(\"ship's company\", \"company\")"                            
  [6] "company"
  </code></pre>
  
  <p>Could someone kindly help me to solve this problem.
  Many thanks.</p>