
...and I could smell German chocolate cake,
which is my favorite.
The Big Bang Theory Season 1, Episode 16

No, I don't know German.
The Big Bang Theory Season 2, Episode 3

and my bowel movements run
like a German train schedule.
The Big Bang Theory Season 5, Episode 10

Like reenacting the ancient German practice
of trial by combat.
The Big Bang Theory Season 8, Episode 19

Unless they're German,
The Big Bang Theory Season 7, Episode 12