What your tyres will do on the road (5)
I believe the answer is:
tread
'what your tyres will do on the road' is the definition.
The definition suggests a singular noun which matches the answer.
'do on the road' is the wordplay.
'do' becomes 'ea' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'on' means one lot of letters goes inside another.
'the' becomes 't' (the is pronounced as a 't' sound in some dialects).
'road' becomes 'rd' (abbreviation).
't'+'rd'='trd'
'ea' going inside 'trd' is 'TREAD'.
Can you help me to learn more?
(Other definitions for tread that I've seen before include "way of dancing" , "Walk or step like pattern on tyre" , "Part of flight" , "Grooves on tyre" , "Rated (anag)" .)