19岁用英语怎么说

19岁用英语可以说成 "nineteen years old"。"Nineteen" 是英语中 19 的数字词，"years old" 是用来表示年龄的常见短语。例如：
She is nineteen years old.
He turned nineteen last month.
At nineteen, I was still figuring out what I wanted to do with my life.
希望这些例句能对你有所帮助。