I agree. I interpret "you don't have to worry with strings with less than two characters" to mean "if a string has less than two characters, do not modify it." This understanding implies that you must ensure that you do not modify strings if they contain only one character, which requires a check. If they meant "all strings passed in will have at least 2 characters," they should have said that.

Yes you should ;-)

When I print the string, I put single quotation marks into the string.
The issue is fixed by removing the single quotation marks in the string returned.

congrats. I tried to print out the list and got the same required result. Then, I use return statement, but I still got the error:

Must work with many names: "'Bart, Lisa, Maggie, Homer & Marge'" should equal 'Bart, Lisa, Maggie, Homer & Marge'

Do you have any idea to fix the issue? Thank you