String first =  "The quick brown fox jumped.";
String second = "The quick brown fox jumped, and was happy.";
// magic goes here
String intended_outcome = "The quick brown fox jumped, and was happy";

String first =  "Hello there. The quick brown fox jumped.";
String second = "The quick brown fox jumped, and was happy.";
// magic goes here
String intended_outcome = "Hello there, The quick brown fox jumped, and was happy";