They work hard yet easily go unnoticed. But these unsung heroes are willing to give a helping hand even at the cost of their summer vacations.

It is tiring, but it is also worthwhile to be a volunteer at the 17th China International Fair for Investment and Trade, said Li Lifeng a student at a local college in Xiamen.

Li has worked for more than 50 days at the organizing committee's exhibitor group preparing for the annual event, which began on Sept 8.