Together with Lang, crazy about duck? (5)
I believe the answer is:
along
'together' is the definition.
(I've seen this in another clue)
'lang crazy about duck?' is the wordplay.
'crazy' indicates an anagram.
'about' indicates putting letters inside.
'duck?' becomes 'o' (resembles zero - 'duck' in cricket).
'lang' anagrammed gives 'alng'.
'alng' placed around 'o' is 'ALONG'.
'with' acts as a link.
(Other definitions for along that I've seen before include "(Going) in company (with others)" , "From one end to the other" , "With a forward motion: in accompaniment" , "Lining" , "Lengthwise" .)