If a try works out, give formal consent (6)
I believe the answer is:
ratify
'formal consent' is the definition.
'ratify' can be an answer for 'consent' (thesaurus). I'm not certain of the 'formal' bit.
'if a try works out' is the wordplay.
'works out' indicates anagramming the letters (I've seen 'working out' mean this (an anagram must be worked out from the letters)).
'if'+'a'+'try'='ifatry'
'ifatry' is an anagram of 'RATIFY'.
'give' is the link.
Can you help me to learn more?
(Other definitions for ratify that I've seen before include "Approve and formally accept" , "Authorise" , "Formally confirm" , "Affirm" , "Sanction" .)