join() : The join() method joins the collection's values with a string:collect(['a', 'b', 'c']).join(', ');
// 'a, b, c'
collect(['a', 'b', 'c']).join(', ', ', and ');
// 'a, b, and c'
collect(['a', 'b']).join(', ', ' and ');
// 'a and b'
collect(['a']).join(', ', ' and ');
// 'a'
collect([]).join(', ', ' and ');
// ''