Accompany young woman in dancing tango (3,5)
I believe the answer is:
tag along
'accompany' is the definition.
(tagging along is a kind of accompanying)
'young woman in dancing tango' is the wordplay.
'young woman' becomes 'gal' ('gal' can be a synonym of 'young woman').
'in' is an insertion indicator.
'dancing' indicates anagramming the letters.
'tango' anagrammed gives 'taong'.
'gal' inserted inside 'taong' is 'TAG ALONG'.
(Other definitions for tag along that I've seen before include "Follow" , "go with the flow" .)