Crossword Genius

Yes, saw a Cambodian for treat­ment for a very long time (5,4,3,1,3)

Ross

I believe the answer is:

since adam was a boy

'for a very long time' is the definition.

'yes saw a cambodian for treatment' is the wordplay.
'for treatment' indicates an anagram (I've seen this in other clues).
'yes'+'saw'+'a'+'cambodian'='yessawacambodian'
'yessawacambodian' with letters rearranged gives 'SINCE ADAM WAS A BOY'.

I've seen this clue in The Guardian.
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