Die Linie ist lang.

Because Linie is a feminine noun in German. German nouns have grammatical gender, and Linie is learned as die Linie.

In this sentence, Linie is the subject, so it is in the nominative case. The nominative singular article for feminine nouns is die.

So:

• der = masculine nominative singular
• die = feminine nominative singular
• das = neuter nominative singular

Here, die means the.

German die can have different jobs in different sentences, but in Die Linie ist lang, it is simply the definite article for the noun Linie.

So the structure is:

• die = the
• Linie = the noun
• together: die Linie = the line

In German, all nouns are capitalized, not just proper names.

So Linie starts with a capital L because it is a noun. This is a basic spelling rule in German.

Examples:

• die Linie
• das Haus
• der Tisch

But adjectives and verbs are normally not capitalized:

• lang
• ist

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

The subject is die Linie, which is singular: the line. So German uses ist:

• ich bin = I am
• du bist = you are
• er/sie/es ist = he/she/it is

Since die Linie is a singular noun, the correct form is ist.

Because lang is being used after the verb ist, so it is a predicate adjective. In German, predicate adjectives usually do not take endings.

So:

• Die Linie ist lang. = adjective after ist → no ending

But when the adjective comes before a noun, it usually does take an ending:

• die lange Linie = the long line

This is an important difference:

• Die Linie ist lang.
• Die lange Linie ...

Here, lang is an adjective.

It describes a quality of the noun Linie. In English, long does the same job in The line is long.

In this sentence, lang is specifically a predicate adjective because it comes after ist and describes the subject.

This is the normal German word order for a simple statement:

1. subject: Die Linie
2. verb: ist
3. description/complement: lang

German main clauses usually place the finite verb in second position. Here the subject comes first, so the verb comes right after it.

That gives:

• Die Linie
  • ist
    • lang

Yes, you can, but it is less neutral and sounds more emphatic, poetic, or marked.

Normal everyday word order is:

• Die Linie ist lang.

If you say:

• Lang ist die Linie.

you are putting lang first for emphasis. German still keeps the finite verb in second position, so ist stays second.

A learner should usually prefer Die Linie ist lang unless there is a special reason to emphasize lang.

Linie is pronounced roughly like LEE-nee-uh, with three syllables:

• Li-ni-e

A more precise pronunciation is [ˈliːni̯ə].

Important points:

• the first syllable Li- is stressed
• the ie in the first syllable sounds like a long ee
• the ending is not like English line; it is a separate German noun pronounced quite differently

Lang is pronounced roughly like lahng.

A more precise pronunciation is [laŋ].

A few helpful notes:

• the a is broad, not like the a in English cat
• the ng is like the sound in English sing
• the final g is not strongly pronounced like a separate hard g

Yes. Linie and line are close in meaning, but they are not pronounced the same.

German Linie often means:

• a drawn line
• a route or line, such as a bus or train line
• a line in a design or shape

So it is a useful word, but you still need to learn it as the German noun die Linie.

Yes. Lang often means long in the sense of physical length, but it can also describe time in other contexts.

For example:

• Die Linie ist lang. = physical length
• Der Film ist lang. = the film is long
• Der Tag ist lang. = the day is long

So the core idea is long, but the exact sense depends on the noun being described.

Usually no, if you specifically mean that the line has a lot of length.

• lang = long
• groß = big / large / tall, depending on context

A line is normally described as lang, not groß.

So:

• Die Linie ist lang. = natural
• Die Linie ist groß. = unusual or unnatural in most contexts

The plural of die Linie is die Linien.

So:

• singular: die Linie
• plural: die Linien

Then the sentence would change like this:

• Die Linie ist lang. = The line is long.
• Die Linien sind lang. = The lines are long.

Notice that the verb changes too:

• singular: ist
• plural: sind