Possible Clues:

• In sheer panic, are going off to practise
• Prepare for a stage production
• Army men on funeral car run over the lines
• Just about the last sort of transport to practise
• Practise before performing in public
• Practice on car when you're late
• That's just about the last sort of transport you'd be having to practise with
• Practise about the last sort of transport you'd need
• Practice in theatre
• Practise as for play