4 sentences for 须 (xū — must)

1. 夫学须静也，才须学也。

   fú xué xū jìng yě, cái xū xué yě.

   Learning requires stillness, and talent requires learning.

   Source: Dong Chinese Dictionary

2. 这种药须饭后服用。

   zhè zhǒng yào xū fàn hòu fú​yòng.

   This medicine must be taken after meals.

   Source: Dong Chinese Dictionary

3. 凡事须得致意，不可马虎。

   fán shì xū děi zhì​yì, bù kě mǎ​hu.

   One must be attentive to everything and not be careless.

   Source: Dong Chinese Dictionary

4. 尔等须尽力而为。

   ěr děng xū jìn​lì'ér​wéi.

   You all must do your best.

   Source: Dong Chinese Dictionary