In the long grass, the French made unsteady progress (6)
I believe the answer is:
reeled
'made unsteady progress' is the definition.
The definition and answer can be both to do with motion as well as being past participle verbs.
Perhaps there's an association between them I don't understand?
'in the long grass the french' is the wordplay.
'in the' means one lot of letters goes inside another.
'long grass' becomes 'reed' (type of grass plant).
'the french' becomes 'le' ('the' in French).
'reed' going around 'le' is 'REELED'.
Can you help me to learn more?
(Other definitions for reeled that I've seen before include "Felt giddy, staggered" , "Staggered (at a Highland ball?)" , "'Staggered, spun around (6)'" , "Felt giddy or bewildered" , "Staggered in a dance perhaps" .)