The World Health Organization gave a warning to the public without any ______when the virus of H1N1 hit Mexico in April, 2009. 

If we keep wasting so much energy, _____are that our oil wells will dry up and the environment will be destroyed.

They are said to have developed a new ______ to teaching, which is said to improve classroom teaching greatly. 

That she hadn’t kept her ____ on her work resulted in the failure.

Global warming is a big _______ for all and it’s important to raise awareness about climate change.