text: var myStr = "I think therefore I am.";
  print("\nOriginal string: ");
  print(myStr);
  print("\nFinding the substing think: ")
  if (myStr.indexOf("think") != -1){
    print(myStr + " contains think");
  }
  print("\nReplacing the substing think with feel: ")
  var newStr = myStr.replace("think", "feel");
  print(newStr);
  print("\nConverting the phrase into an array: ")
  var myArr = myStr.split(" ");
  printjson(myArr);