I will not speak unless _______.

—Why does the lake smell terrible?—Because large quantities of water______.          

A new library        downtown. They hope to complete it by the end of this year.

(2014·安徽七校联考)It is difficult for children to change their eating habit later in life.________，parents should encourage healthy eating from an early age.

The film Let the Bullets Fly _____ a great success and brought in a large profit to the cinema.