He gets only two-thirds of basic education in German (4)
I believe the answer is:
herr
This clue could be a double definition.
'he gets only two-thirds of basic education' is the first definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'german' is the second definition.
(German equivalent to Mr)
'in' is the link.
Can you help me to learn more?
(Other definitions for herr that I've seen before include "Mister in German" , "German man's title" , "European guy" , "A German gentleman" , "Form of address for German male" .)