In Level 1 of Ulpan La-Inyan we teach the verb, it hurts (זֶה כּוֹאֵב - zeh koh-EHV).
The word for ache or pain is כְּאֵב (keh-EHV).
Holocaust Day (today), or יוֹם הַשּׁוֹאָה (yohm hah-shoh-AH) in Hebrew (means literally, the day of the disaster or conflagration), is a יוֹם כְּאֵב לְאוּמִי (yohm keh-EHV le-oo-MEE) - a national day of pain.
I walked in the streets of Jerusalem tonight, noting that the restaurants were closing in homage to this day of כאב לאומי, and I began to feel it myself.
My thought now go to my dear grandmother, who survived Auschwitz but lost her parents and four brothers and sisters there. I don't know how she bears the pain.
Here's Oyf Pripetshok (I can't spell in actual Yiddish), a song played in Schindler's List, a song I found quite moving, even agonizing. Here are the lyrics, and the video follows.
I'll be playing songs like these as well as Israeli ones, with explanations, on my radio show today on RustyMike. Tune in at 3pm Israel time.