speak from memory

例句：

1. 1. She spoke from memory about her childhood adventures.
   她即兴地讲述了她的童年冒险故事。
2. 2. The teacher asked the students to speak from memory before the exam.
   考试前，老师要求学生们背诵记忆。
3. 3.He related a story from memory that had never been told before.
   他回忆起一个从未被讲述过的故事。