Thank you for your question. My name is Steve and I am a fully qualified vehicle technician, hopefully I can help.
From the data I have the clutch on the 2008 1.1 Hyundai is hydraulically operated. This means that if it has suddenly gone slack then the hydraulic system may have a leak and lost fluid. The fluid for the clutch is fed from the brake fluid reservoir, but if it has lost fluid it will need bleeding out to restore the clutch pedal.
The problem may need a new clutch slave cylinder or master cylinder to resolve the problem.
The clutch slave cylinder on the Getz is externally fitted and so if it is this then the job is not a big one.
Provided the clutch has felt fine up to this point then hopefully the actual clutch is ok.
I can sometimes be the case that when the clutch is badly worn the clutch slave cylinder needs to travel further and this can allow it to leak, but hopefully this is not the case with your other half's Hyundai.
I hope this answers your question but do please feel free to ask me any further details.
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