repetition of symbol

例句：

1. 1. The teacher repeated the lesson several times to ensure understanding.
   老师多次重复讲解，确保学生理解。
2. 2. The scientist repeated his experiments to check for any errors.
   科学家重复实验以检查是否有错误。
3. 3. The artist repeated the strokes of the brush to create a new piece.
   艺术家重复画笔的笔触来创作新的画作。