Yiddish has all sorts of interesting characteristics, and came into its own just before and after a great migration of Jews from Europe to the US. But it was mostly downhill from there because one of its major components is the German language, and without it Yiddish loses much of its impulse.
English just does not provide the same momentum. It does not contribute to Yiddish as much as absorb from it.
One of its more interesting features is its “maledicta”, cursing and swearing, which starts out as a blessing before it turns into a curse. For example (English translation):
“May he inherit a hotel with a hundred rooms, and then may he have a heart attack in every one of those rooms.”
A Jewish entertainer? Get out of here!
Homer Simpson
There is an excellent “Great Performances” ran just this am, about the the Thomashevskys. WEDU. It might run tomorrow also, and I think you can watch the streaming performances on their website. It is fascinating - the song Das Pintele Yid mesmerized me.
http://video.pbs.org/video/2216468713
53 minute mark (If the link still works - these things change)
In every land, in every place
The Jew hears only one thing
You are a Jew, go away.
You are an outsider
The Jew wanders, doesn’t get tired.
The spark of Jewishness is in his heart.
He laughs at his enemies
When God is with him,
Who can do him harm?
Many time little Israel’s spirit is broken
He bends before the slightest wind
But the strongest storm cannot uproot
The little, beautiful spark
The spark of Jewishness is very dear
Honor and pride
It gives to you.
Value, respect, and guard it.
Little Jew, that spark is your crown.
You have suffered much for it,
They wore out your limbs
Tortured your brothers,
Everyone bathed in your blood
There are endless lies against that spark
But it is always courageous
The wise Jew laughs at his enemies.