2 sentences

1. 他们听到一条狗在外面汪汪叫。

   tā​men tīng dào yī tiáo gǒu zài wài​miàn wāng​wāng jiào.

   They heard a dog barking outside.

   Source: AI Challenger 2017

2. 那条狗突然开始对我们汪汪叫。

   nà tiáo gǒu tū​rán kāi​shǐ duì wǒ​men wāng​wāng jiào.

   The dog suddenly started barking at us.

   Source: AI Challenger 2017