Willing to study on the Fourth of July (5)
I believe the answer is:
ready
'willing' is the definition.
(associated in meaning)
'study on the fourth of july' is the wordplay.
'study' becomes 'read' (synonyms).
'on' says to put letters next to each other (in a down clue, letters appear on others).
'the fourth of july' becomes 'y' (fourth letter of the word 'July').
'read'+'y'='READY'
'to' is the link.
(Other definitions for ready that I've seen before include "Primed" , "At hand" , "Cash; within reach" , "All set to go" , "bread" .)