Final answer:
Jewish men, including the student's uncle Herbert, were forced to take the middle name "Israel" in Germany to identify them as Jews, while Jewish women were assigned "Sara" as part of the Nuremberg Laws of 1935.
Step-by-step explanation:
The middle name that your uncle Herbert and all Jewish men in Germany were forced to take to identify them as Jewish was "Israel" for men and "Sara" for women. This measure was part of the wider array of legal discriminations set by the Nuremberg Laws of 1935. The Nuremberg Laws stripped Jews of their German citizenship and implemented numerous social restrictions. They were also required to register their property, which was then systematically expropriated. Anti-Semitic laws increased over time, progressively excluding Jews from public life, confiscating their property, and eventually leading to the horrors of the Holocaust.