How many thieves were there? My dear, a score! (5,4)

I believe the answer is:

forty love

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'how many thieves were there? my' is the definition.
I don't know anything about this answer so I cannot tell whether this works.

'dear a score' is the wordplay.
'dear' becomes 'forty' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'a score' becomes 'love' (love is a kind of score).
'forty'+'love'='FORTY LOVE'

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