Life must be lived as play.    From LearnThat.org.  [Plato (c.427-347 BC), Greek philosopher, student of Socrates, teacher of Aristotle.]

If you want to create an object of a subalbum the name must include the parent album name (s) like.    From Wordnik.com.  [Zenphoto] Reference

A book that is must reading.    From Wordnet, Princeton University. 

Seat belts are an absolute must.    From Wordnet, Princeton University. 

So your name must be the best amongst your market.    From Wordnik.com.  [Recently Uploaded Slideshows] Reference

Of those five, at least two of the titles must have shipped.    From Wordnik.com.  [Gamasutra Feature Articles]