tā zhànqǐlái de shíhou tūrán gǎndào yī zhèn xuànyùn.
She suddenly felt a bout of dizziness when she stood up.
Tips
mistakes
眩晕 is pronounced xuànyùn in mainland China, but xuànyūn in Taiwan. Don't confuse 眩 (dizzy) with 炫 (dazzling/show off) — they look similar but have different meanings.