Very many of you on the beach? (9)
I believe the answer is:
thousands
'very many' is the definition.
'thousands' can be an answer for 'many' (thesaurus). I am not sure about the 'very' bit.
'you on the beach?' is the wordplay.
'you' becomes 'thou' (historical second person pronoun).
'on' says to put letters next to each other (in a down clue, letters appear on others).
'the beach?' becomes 'sands' (sands can mean a beach area).
'thou'+'sands'='THOUSANDS'
'of' acts as a link.
Can you help me to learn more?
(Other definitions for thousands that I've seen before include "a lot" , "Crowds" , "Dan shouts out at many hundreds" , "large sum?" , "1000s" .)