1 sentence

1. 后来，当她的鞋子变脏时，她注意到有一处保持干净。

   hòu​lái, dāng tā de xié​zi biàn zāng shí, tā zhù​yì dào yǒu yī​chù bǎo​chí gān​jìng.

   Later, when her shoes got dirty, she noticed that one spot stayed clean.

   Source: CCMatrix