3 sentences for 虚 (xū — false)

1. 眼见为实，耳听为虚。

   yǎn​jiàn wéi shí, ěr tīng wéi xū.

   Seeing is believing, but hearing is not necessarily true.

   Source: Dong Chinese Dictionary

2. 请在虚线上签名。

   qǐng zài xū xiàn shàng qiān​míng.

   Please sign on the dotted line.

   Source: Dong Chinese Dictionary

3. 人生苦短，我们不该虚度光阴。

   rén​shēng kǔ duǎn, wǒ​men bù gāi xū dù guāng​yīn.

   Life is short; we shouldn't idle away our time.

   Source: Dong Chinese Dictionary