Die Schneiderkreide markiert die Stoffkante.

Because both nouns are feminine singular:

• die Schneiderkreide = the tailor’s chalk
• die Stoffkante = the fabric edge

In this sentence:

• die Schneiderkreide is the subject → nominative
• die Stoffkante is the direct object → accusative

For feminine singular nouns, the article is die in both the nominative and accusative, so the form does not change.

You identify them mainly by meaning and verb logic here:

• markiert = marks
• the thing doing the marking is die Schneiderkreide
• the thing being marked is die Stoffkante

So:

• Die Schneiderkreide = subject
• die Stoffkante = object

Because both nouns are feminine and both use die, the articles alone do not show the difference in this sentence.

Markiert is the 3rd person singular form of the verb markieren.

The subject is die Schneiderkreide, which is singular, so the verb must match it:

• ich markiere
• du markierst
• er/sie/es markiert

So Die Schneiderkreide markiert ... means The tailor’s chalk marks ...

German very often makes compound nouns by joining words together.

Schneiderkreide is made from:

• Schneider = tailor
• Kreide = chalk

Together, Schneiderkreide means tailor’s chalk or tailoring chalk.

This is extremely common in German. The last part usually tells you the main category of the thing:

• Kreide is the basic noun
• Schneider- describes what kind of chalk it is

Not exactly in grammar, even though that is a natural English translation.

In German, Schneiderkreide is just a compound noun, not a possessive structure. German often uses compounds where English might use:

• tailor’s chalk
• chalk for tailors
• tailoring chalk

So it is not built like des Schneiders Kreide. It is simply one noun: die Schneiderkreide.

Stoffkante is another compound noun:

• Stoff = fabric/material
• Kante = edge

So die Stoffkante means the fabric edge or the edge of the fabric.

Again, the last part is the main noun:

• Kante is the basic thing
• Stoff- tells you what kind of edge it is

The sentence follows the very common German pattern:

Subject + verb + object

• Die Schneiderkreide = subject
• markiert = verb
• die Stoffkante = object

So it is a very straightforward main clause.

German main clauses usually put the finite verb in second position, and that is exactly what happens here.

Yes. German allows other elements to come first, as long as the finite verb stays in second position in a main clause.

For example:

• Die Stoffkante markiert die Schneiderkreide.

This would sound like The fabric edge marks the tailor’s chalk, so the meaning changes unless context makes it clear otherwise.

You could also say:

• Die Stoffkante markiert die Schneiderkreide nicht.

But for the original meaning, Die Schneiderkreide markiert die Stoffkante is the natural basic order.

Yes, markiert here is present tense.

German present tense can often cover both:

• The tailor’s chalk marks the fabric edge
• The tailor’s chalk is marking the fabric edge

German usually does not need a separate form like English is marking unless you want to add extra wording for emphasis.

A rough English-friendly guide is:

SHNIGH-der-KRY-duh

More carefully:

• Sch sounds like sh
• ei sounds like English eye
• krei also has eye
• the final -e in Kreide is a weak uh sound

And markiert is roughly:

mar-KEERT

with the stress on the second syllable.

Yes.

• die Schneiderkreide can be used as a mass noun, but if pluralized in a context about different pieces/types, it may appear as die Schneiderkreiden
• die Stoffkante → die Stoffkanten

Articles would then depend on case and number. For example:

• die Stoffkante = singular
• die Stoffkanten = plural

A useful thing to notice is that die is also the plural nominative and accusative article for all genders, so German learners often need to rely on context and noun endings too.