wear thin

动词 wear thin:

1. deteriorate through use or stress
   同义词：wear, wear off, wear out, wear down

1. The teacher's patience began to wear thin when he saw that no one knew the lesson.
   老师发觉大家对功课一无所知，就渐渐不耐烦起来。
2. As a result, nacre thickness is sometimes just a cosmetic layer that can wear thin over time.
   所以真珠质的厚度就像脸上化妆品，不久就会磨薄了。
3. The joke began to wear thin when you heard it too many times.
   这个笑话因为听得遍数太多不那么吸引人了。