Strong line taken at a trade exhibition? (4,5)

I believe the answer is:

firm stand

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'at a trade exhibition?' is the definition.
I don't know anything about this answer so I can't judge whether this works.

'strong line' is the wordplay.
'strong' becomes 'firm' (synonyms).
'line' becomes 'stand' (I am not sure about this - if you are sure you should believe this answer much more).
'firm'+'stand'='FIRM STAND'

'taken' is the link.

Can you help me to learn more?

I've seen this clue in The Globe and Mail.

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