3 sentences

1. 水下世界真是引人入胜。

   shuǐ​xià shì​jiè zhēn​shi yǐn​rén​rù​shèng.

   The underwater world is really fascinating.

   Source: AI Challenger 2017

2. 想象一下，世界将会多么不同。

   xiǎng xiàng yī​xià, shì​jiè jiāng​huì duō​me bù​tóng.

   Imagine how different the world would be.

   Source: CCMatrix

3. 1、早在中世纪，许多人就相信火山是进入炽热的地下世界的入口。

   1, zǎo​zài zhōng​shì​jì, xǔ​duō rén jiù xiāng​xìn huǒ​shān shì jìn​rù chì​rè de dì​xià shì​jiè de rù​kǒu.

   During the Middle Ages, many people thought volcanoes were the entrance to the fiery underworld.

   Source: CCMatrix