1.  They take no account of the unpaid labour service of volunteers, which is the essential resource element of the voluntary sector.

2.  The computer laboratory is an essential resource for students.

3.  Anti-riot police must be provided with essential resources -- manpower, training and equipment -- to do their job properly.

4.  In addition, information describing actions by foreign governments and businesses are essential resources.

5.  Through waste treatment, it can recover essential resources materials like lead and gypsum for the manufacturing industry which currently imports the materials.