Definition: In this task, you need to generate an appropriate title for the given summary of some paragraph. The generated title must be short and should include the main topic of the given text. Your summary should be less than 20 words long.
Input: Sustainable, renewable, green: the buzz words of the environmentalists figured large at this week's Dubai Air Show. At the last show two years ago, such things barely registered.

Dubai Air Show: The challenges for us all in flying green