They're useful for audition and in rehearsal

I believe the answer is:

ears

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'they're useful for audition' is the definition.
The definition suggests an adverb but the answer is not.

'in rehearsal' is the wordplay.
'in' indicates a hidden word.
'EARS' can be found hidden inside 'rehearsal'.

'and' acts as a link.

Can you help me to learn more?

(Other definitions for ears that I've seen before include "Lugs (colloq.)" , "Seed-bearing parts of corn" , "Spikes (of cereals)" , "One's hearing aids" , "Walls are said to have them" .)

I've seen this clue in the Evening Standard.

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