Das Kettenöl dient dem Schutz.

The chain oil serves as protection.

Breakdown of Das Kettenöl dient dem Schutz.

• das Kettenöl: the bicycle-chain oil
• dienen: to serve a purpose
• der Schutz: protection

Questions & Answers about Das Kettenöl dient dem Schutz.

Why is it dem Schutz and not der Schutz or den Schutz?

Because the verb dienen takes the dative case.

The basic pattern is:

• etwas dient jemandem / etwas dient etwas
  = something serves someone / serves some purpose

So in:

• Das Kettenöl dient dem Schutz.

dem Schutz is dative singular.

A quick breakdown:

• der Schutz = nominative
• den Schutz = accusative
• dem Schutz = dative

Since Schutz is a masculine noun, its dative singular form is dem Schutz.

What does dienen mean here?

Here, dienen means to serve, to be used for, or to be intended for.

So Das Kettenöl dient dem Schutz literally means something like:

• The chain oil serves protection
• more naturally: The chain oil is for protection
• or: The chain oil helps protect

In German, dienen is often used in a slightly formal or technical way to explain a function or purpose.

Examples:

• Das Werkzeug dient der Reparatur.
  = The tool is used for repair.
• Die Brille dient dem Schutz der Augen.
  = The glasses serve to protect the eyes.

Is Kettenöl one word because German likes compounds?