Happen again to be somewhat more curious (5)
I believe the answer is:
recur
'happen again' is the definition.
(I've seen this in another clue)
'somewhat more curious' is the wordplay.
'somewhat' indicates a hidden word.
'RECUR' is hidden in the letters of 'more curious'.
'to be' acts as a link.
(Other definitions for recur that I've seen before include "expected to return" , "Happen repeatedly" , "Repeat" , "Happen again (5)" , "Return to mind" .)