topThreeWords("In a village of La Mancha, the name of which I have no desire to call to mind, there lived not long since one of those gentlemen that keep a lance in the lance-rack, an old buckler, a lean hack, and a greyhound for coursing. An olla of rather more beef than mutton, a salad on most nights, scraps on Saturdays, lentils on Fridays, and a pigeon or so extra on Sundays, made away with three-quarters of his income."); // ["a", "of", "on"]
topThreeWords("e e e e DDD ddd DdD: ddd ddd aa aA Aa, bb cc cC e e e"); // ["e", "ddd", "aa"]
topThreeWords(" //wont won't won't"); // ["won't", "wont"]
topThreeWords(" , e .. "); // ["e"]
topThreeWords(" ... "); // []
topThreeWords(" ' "); // []