Das Reparaturmaterial liegt jetzt auf der freien Werkbank.

Because Reparaturmaterial is a neuter noun, so it takes the article das in the nominative singular.

A helpful thing to notice is that Reparaturmaterial is a compound noun:

• Reparatur = repair
• Material = material

In German, the last part of a compound usually determines the gender. Since das Material is neuter, das Reparaturmaterial is neuter too.

Here it is singular.

It often works like a collective or mass noun, similar to English repair material or repair supplies, depending on context. Even if it refers to several physical items, German can still treat it as one general category of material.

That is why the verb is liegt and not liegen.

German often uses specific position/location verbs where English might simply use is.

Here, liegen means something like:

• to be lying
• to be located lying down
• to rest somewhere

So Das Reparaturmaterial liegt ... is more natural in German than Das Reparaturmaterial ist ... in this context.

German commonly distinguishes between:

• liegen = to lie
• stehen = to stand
• sitzen = to sit

For objects, the choice often depends on how the thing is situated, or simply on normal idiomatic usage.

Because liegen is the normal verb for something that is lying flat or simply resting on a surface.

A workbench is a horizontal surface, so materials placed on it are naturally described with liegen.

Compare:

• Das Buch liegt auf dem Tisch. = The book is lying on the table.
• Die Flasche steht auf dem Tisch. = The bottle is standing on the table.

So with Reparaturmaterial, liegt sounds natural.

Because this sentence describes a location, not a movement toward a destination.

The preposition auf is a two-way preposition. That means it can take:

• dative for location: where?
• accusative for direction: where to?

Here, the material is already there:

• Das Reparaturmaterial liegt auf der freien Werkbank.

So we use dative: auf der freien Werkbank.

If you were talking about moving it onto the bench, you would use accusative:

• Ich lege das Reparaturmaterial auf die freie Werkbank.

Because der here is not nominative masculine. It is dative feminine singular.

The noun is die Werkbank in the basic dictionary form, because Werkbank is feminine.

Its forms are:

• nominative: die Werkbank
• accusative: die Werkbank
• dative: der Werkbank
• genitive: der Werkbank

So after auf in a location meaning, we need the dative form:

• auf der Werkbank

Because the adjective has to match the noun’s gender, number, case, and article pattern.

Here we have:

• Werkbank = feminine singular
• after auf in a location sense = dative
• with the definite article der

So the adjective ending must be -en:

• auf der freien Werkbank

This is a standard adjective ending after a definite article in the dative singular.

Compare:

• nominative: die freie Werkbank
• accusative: auf die freie Werkbank
• dative: auf der freien Werkbank

No. Here frei means available, unoccupied, or not currently in use.

So die freie Werkbank means something like:

• the free workbench
• the available workbench
• the unoccupied workbench

It does not mean the workbench costs nothing.

Because German main clauses normally put the finite verb in second position.

The sentence structure is:

• Das Reparaturmaterial = position 1
• liegt = position 2
• jetzt = later in the sentence
• auf der freien Werkbank = location phrase

So the sentence follows the normal verb-second pattern.

You can think of it like this:

• Das Reparaturmaterial | liegt | jetzt | auf der freien Werkbank

Yes, German adverbs are fairly flexible, although some positions sound more natural than others depending on emphasis.

For example:

• Das Reparaturmaterial liegt jetzt auf der freien Werkbank.
  Neutral and natural.

• Jetzt liegt das Reparaturmaterial auf der freien Werkbank.
  Emphasizes now.

• Das Reparaturmaterial liegt auf der freien Werkbank jetzt.
  Usually much less natural in standard German.

So yes, jetzt can move, but the original version is a very normal word order.

Because all German nouns are capitalized.

So in this sentence, these words are capitalized because they are nouns:

• Reparaturmaterial
• Werkbank

This is one of the most noticeable spelling rules in German.

Yes—German very often forms new nouns by combining existing nouns into a compound noun.

So instead of writing something like repair material as two separate words, German usually writes:

• Reparaturmaterial

This is completely normal. The final part usually carries the core meaning, and the earlier part describes it.

Other examples:

• Werkbank = Werk
  • Bank
• Haustür = house door
• Küchentisch = kitchen table

A useful way to look at it is:

• Subject: Das Reparaturmaterial
• Verb: liegt
• Time: jetzt
• Place: auf der freien Werkbank

That gives:

• Das Reparaturmaterial liegt jetzt auf der freien Werkbank.

This matches a very common German order in neutral statements: subject + verb + time + place.

It is not the only possible order, but it is a very common and natural one.

Yes, that would be understandable, and in some contexts it may sound fine. But liegt is usually more idiomatic because it gives a clearer sense of the material’s physical position.

So:

• ist = more general existence/location
• liegt = more specifically located lying there

German often prefers the more specific verb.

You mostly learn it as part of a group. Common two-way prepositions include:

• an
• auf
• hinter
• in
• neben
• über
• unter
• vor
• zwischen

They use:

• dative for location: where?
• accusative for direction: where to?

So in this sentence:

• liegt auf der Werkbank = location → dative

But:

• legt auf die Werkbank = movement toward it → accusative

Not always. Very often it does suggest that something is lying rather than standing, but in practice German uses liegen quite broadly for many objects that are resting somewhere.

So you should learn it partly as a matter of usage, not only strict physical logic.

For example:

• Das Buch liegt auf dem Tisch.
• Die Kleidung liegt auf dem Bett.
• Das Werkzeug liegt in der Schublade.

So in your sentence, liegt is a normal and natural choice.