text: function getLetter(s) {
    let letter;
  
    switch (true) {
      case "aeiou".includes(s[0]):
        letter = "A";
        break;
      case "bcdfg".includes(s[0]):
        letter = "B";
        break;
      case "hjklm".includes(s[0]):
        letter = "C";
        break;
      case "mpqrstvwxyz".includes(s[0]):
        letter = "D";
        break;
    }
  
    return letter;
  }
  