Inform university a German is joining about end of April (4,2)
I believe the answer is:
clue in
'inform' is the definition.
(I've seen this before)
'university a german is joining about end of april' is the wordplay.
'university' becomes 'u'.
'a german' becomes 'ein' ('a' in German).
'is joining' says to put letters next to each other.
'about end of april' becomes 'cl' (I can't justify this - if you can you should believe this answer much more).
'u'+'ein'='uein'
'uein' put after 'cl' is 'CLUE IN'.
Can you help me to learn more?
(Another definition for clue in that I've seen is " Inform".)