Sappers given vehicle to prepare for further use (7)
I believe the answer is:
recycle
'use' is the definition.
(recycling is a kind of using)
'sappers given vehicle' is the wordplay.
'sappers' becomes 'RE' (nickname for the Royal Engineers).
'given' means one lot of letters go next to another.
'vehicle' becomes 'cycle' (cycle is a kind of vehicle).
're'+'cycle'='RECYCLE'
'to prepare for further' is the link.
This may not be correct. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for recycle that I've seen before include "Process for further use" , "Convert waste to new usage" , "Keep and use again" , "Process for re-use" , "Make new use of" .)