n.[U][(+of)]

1. 保存
2. （對自然資源的）保護，管理
   Conservation is one way to make sure we have enough energy in the future.

   對自然資源的保護是保證我們將來有足夠的能源的一種辦法。

3. 【物】守恆，不滅
   conservation of mass

   質量守恆

n.

1. preservation or restoration of the natural environment and wildlife.
   ▸preservation and repair of archaeological, historical, and cultural sites and artefacts.
2. careful use of a resource.
3. Physics  the principle by which the total value of a quantity remains constant in a system which is not subject to external influence.