Leaders should be matched to the specific function of the group.

This one had a very specific function: informing the authorities if your neighbour was unwell.

The celebrations run over two weeks, with each day serving a specific function.

Mentors and pupils can modify the relationship on their own terms but the structured internet-based correspondence has a specific function.

Then, of course, large pasta shells and pocket pastas, such as tortellini, serve a specific function, as a vessel for their cheese or meat-based filling.