"伤心" (shāngxīn) is the Chinese word for "sad." In Engpsh, you can say "sad" or "heartbroken."

To pronounce "sad," stress the first syllable and say it with a short "a" sound, pke "sad." To pronounce "heartbroken," stress the first syllable and say it with a long "a" sound, pke "hahrt-broh-kuhn."

Here are some example sentences using these words:

"I'm feepng sad today."
"She was heartbroken when her relationship ended."
"His sad face made me want to comfort him."
"The news of her death left him heartbroken."