3 sentences

1. 雪地上留下了成串的足迹。

   xuě​dì shàng liú​xià le chéng​chuàn de zú jì.

   A trail of footprints was left in the snow.

   Source: Dong Chinese Dictionary

2. 事故现场仍然残留着大量的油迹。

   shì​gù xiàn​chǎng réng​rán cán​liú zhe dà​liàng de yóu jì.

   Large amounts of oil stains still remain at the scene of the accident.

   Source: Dong Chinese Dictionary

3. 这种病目前还没有好转的迹象。

   zhè zhǒng bìng mù​qián hái méi​yǒu hǎo​zhuǎn de jì xiàng.

   There are no signs of improvement in this disease yet.

   Source: Dong Chinese Dictionary