Finally, all our sugar supply given to yak? (9)
I believe the answer is:
garrulous
'to yak?' is the definition.
I can't judge whether this defines the answer.
'finally all our sugar supply' is the wordplay.
'finally' says to take the final letters.
'supply' indicates an anagram (in a supple way).
The last letter of 'all' is 'l'.
'l'+'our'+'sugar'='loursugar'
'loursugar' with letters rearranged gives 'GARRULOUS'.
'given' is the link.
Can you help me to learn more?
(Other definitions for garrulous that I've seen before include "Excessively talkative" , "Voluble - oral gurus (anag)" , "Loquacious and voluble" , "Verbose" , "Chatty" .)