It's an advantage for this girl to return (5)
I believe the answer is:
tessa
'it's an advantage for this girl to return' is the definition.
'Tessa' can be an answer for 'girl'. I am not certain of the remainder of the definition.
'it's an advantage for this girl' is the wordplay.
'it's an advantage' becomes 'a' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'for' means one lot of letters go next to another (I've seen this in other clues).
'this girl' becomes 'tess' (girl's name).
'a' put after 'tess' is 'TESSA'.
Can you help me to learn more?
(Other definitions for tessa that I've seen before include "Dahl or Jowell" , "Tax-exempt special savings account" , "Girl" , "Girl's name, forerunner of ISA" , "Girl's name; former savings account" .)