Read the passage and fill the blanks 37 - 40

More and more young people are (37)...... voluntary work abroad. The wild variety of jobs and destinations available is making it an increasingly attractive option for those who have just left school and have a year free before university. Many choose to spend these twelve months working in poor countries. There they will earn little (38)...... no money. But they will be doing something useful – and enjoying the experience.

The work may . (39)..... of helping the local communities, for example by helping to build new road or provide water supplies to isolated rural villages. Other projects may concentrate more on conservation or environmental protection. (40)…. ... kind of job it is, it is certain to be challenging and worthwhile, and an experience that will never be forgotten.