Die SIM-Karte ist neu.

Because Karte is a feminine noun in German, and the article must match the noun’s gender.

• die Karte = the card
• so die SIM-Karte = the SIM card

In German compound nouns, the last part usually determines the gender. Since the final word is Karte, the whole noun is feminine.

The hyphen is standard and very common here. German often uses a hyphen when:

• an abbreviation is combined with a noun
• the writer wants to make a compound easier to read

So SIM-Karte is the normal spelling. You may sometimes see other compound nouns written as one word, but with abbreviations like SIM, the hyphen is preferred.

It is in the nominative case because it is the subject of the sentence.

The basic structure is:

• Die SIM-Karte = subject
• ist = verb
• neu = description

So the sentence is saying something about the SIM card, which makes it the subject.

Because German main clauses usually follow the verb-second rule.

In a normal statement, the finite verb goes in position 2:

• Die SIM-Karte | ist | neu

This is one of the most important word-order patterns in German.

Ist is the third-person singular form of the verb sein (to be).

The present-tense forms are:

• ich bin = I am
• du bist = you are
• er/sie/es ist = he/she/it is
• wir sind = we are
• ihr seid = you are
• sie/Sie sind = they are / you are

Because die SIM-Karte is singular, German uses ist.

Because neu comes after the verb ist and is being used as a predicate adjective. Predicate adjectives in German do not take adjective endings.

So:

• Die SIM-Karte ist neu. = adjective after sein → neu
• die neue SIM-Karte = adjective before the noun → neue

This is a very common difference in German.

Because nouns are capitalized in German.

• Karte is a noun, so it must be capitalized.
• SIM is already capitalized because it is an abbreviation.

So SIM-Karte is written with capitals for both reasons.

Neu is pronounced roughly like noy in English.

A more accurate pronunciation is [nɔʏ].

It rhymes approximately with English boy, though the vowel quality is not exactly the same.

Here it is singular.

You can tell because:

• the article is die for feminine singular in the nominative
• the verb is ist, which is singular

The plural would be:

• die SIM-Karten
• Die SIM-Karten sind neu. = The SIM cards are new.

Yes, in many situations people might say Die SIM ist neu, especially in informal speech, if the meaning is clear.

However, Die SIM-Karte ist neu is more complete and explicit. It is especially useful for learners because it shows the full noun clearly.

In a yes/no question, German usually puts the verb first:

• Ist die SIM-Karte neu?

That is the direct question form of the statement.

You would usually use nicht:

• Die SIM-Karte ist nicht neu. = The SIM card is not new.

Because neu is an adjective, nicht comes before the adjective phrase it negates.

Yes, it is completely natural. It is a simple and correct everyday sentence.

A German speaker might use it in contexts like:

• comparing an old card with a replacement
• checking whether a phone has a new SIM card
• describing a recently issued SIM card

So it is both grammatically correct and realistic in everyday use.