急剧 (jí jù): rapid; sudden

The heavy rain caused the river to rise rapidly, and the villagers were evacuated to a safe place overnight.

After his father passed away, his personality underwent a drastic change, and he became quiet and withdrawn.

As the cold air moved south, the local temperature dropped sharply, and people hurriedly put on thick coats.

After news of the company's bankruptcy spread, the stock price plummeted, and investors suffered heavy losses.