flint pebble

例句：

1. 1. The beach was littered with flint pebbles.
   海滩上散布着燧石卵石。
2. 2. He picked up a flint pebble and examined it closely.
   他捡起一个燧石卵石，仔细观察起来。
3. 3. She used the flint pebble to smooth out her dress.
   她用燧石卵石来磨平她的裙子。