Are finishing repairs in the passage out (5)
I believe the answer is:
exist
'are' is the definition.
('they are' means 'they exist')
'finishing repairs in the passage out' is the wordplay.
'finishing' indicates one should take the final letters (the letter which finishes the word).
'in' means one lot of letters goes inside another.
'the passage out' becomes 'exit' (the way out).
The final letter of 'repairs' is 's'.
's' going into 'exit' is 'EXIST'.
(Other definitions for exist that I've seen before include "Get a life!" , "Have being or continue living" , "quick!" , "Scrape by" , "Survive" .)