Our duty is to ______ their country against both domestic and foreign enemies’ attack.

Though having lived abroad for years, many Chinese still             the traditional customs.

Many journalists were sent to ________ the terrible disaster immediately the earthquake broke out in Sichuan Province on May 12th,2008.

As long as you are sure this plan works, you should ____ with it, whatever happens. 

  At the opening________of the school, our headmaster gave a short speech.