5 sentences

1. 背面有一个数字。

   bèi​miàn yǒu yī gè shù​zì.

   There's a number on the back.

   Source: OpenSubtitles

2. 请在信封背面写上你的地址。

   qǐng zài xìn​fēng bèi​miàn xiě shàng nǐ de dì​zhǐ.

   Please write your address on the back of the envelope.

   Source: Dong Chinese Dictionary

3. 这种纸太薄，墨水都透到背面了。

   zhè zhǒng zhǐ tài báo, mò​shuǐ dōu tòu dào bèi​miàn le.

   This paper is so thin that the ink bleeds through to the other side.

   Source: Dong Chinese Dictionary

4. 请把这张照片翻过来，背面写着拍摄日期。

   qǐng bǎ zhè zhāng zhào​piàn fān guò​lái, bèi​miàn xiě zhe pāi​shè rì​qī.

   Please flip this photo over; the date it was taken is on the back.

   Source: Dong Chinese Dictionary

5. 这枚硬币的背面刻着国徽。

   zhè méi yìng​bì de bèi​miàn kè zhe guó​huī.

   The national emblem is engraved on the back of this coin.

   Source: Dong Chinese Dictionary