title: What command means "do nothing" in a conditional in Bash?
body: <p>Sometimes when making conditionals, I need the code to do nothing, e.g., here, I want Bash to do nothing when <code>$a</code> is greater than "10", print "1" if <code>$a</code> is less than "5", otherwise, print "2":</p>
  
  <pre><code>if [ "$a" -ge 10 ]
  then
  elif [ "$a" -le 5 ]
  then
      echo "1"
  else
      echo "2"
  fi
  </code></pre>
  
  <p>This makes an error though. Is there a command which will do nothing and also not slow down my script?</p>