3 sentences

1. 重力并不总是你的朋友。

   zhòng​lì bìng bù zǒng shì nǐ de péng​you.

   Gravity isn't always your friend.

   Source: OpenSubtitles

2. 地球的重力使物体落向地面。

   dì​qiú de zhòng​lì shǐ wù​tǐ luò xiàng dì​miàn.

   The Earth's gravity causes objects to fall toward the ground.

   Source: Dong Chinese Dictionary

3. 外面没有重力。

   wài​miàn méi​yǒu zhòng​lì.

   There's no gravity out there.

   Source: OpenSubtitles