Not until I began to work ____ how much time I had wasted.

If you meet troubles in your life, you must try to _________the troubles.

When _______ this stone bridge______ ?—In 1935.

The British are not so familiar with different cultures and other ways of doing things, ___________ is often the case in other countries

How do you like the film AVATAR?–– Great! I _______ such a wonderful film before.