"I forgot my umbrella" 是说"我忘记带雨伞了"的正确表达。
来源：这是一句普通的日常英语表达。
例句1:
"I left my umbrella at home. Now I'm getting soaked in the rain." (我把雨伞留在家里了。现在我在雨中淋湿。)
例句2:
"I can't bepeve I forgot my umbrella. I knew it was supposed to rain today." (我不敢相信我忘记带雨伞了。我知道今天会下雨。)