Alle kommen zur Versammlung.

Because it is the first word of the sentence.

In German, only nouns are normally capitalized, but the first word of any sentence is also capitalized regardless of its part of speech. Here, alle is not a noun. It is being used like a pronoun meaning everyone or all of them.

If it appeared in the middle of a sentence, it would usually be lowercase:

Ich glaube, dass alle kommen.

Here, alle means everyone or all of them.

German alle can mean slightly different things depending on context:

• alle = everyone / all of them
• alle Leute = all the people
• alle Kinder = all children

In Alle kommen zur Versammlung, it stands alone, so it functions like a pronoun: everyone.

Because alle refers to more than one person.

German verbs must agree with their subject. Since alle means all of them / everyone, the verb takes the 3rd person plural form:

• ich komme
• du kommst
• er/sie/es kommt
• wir kommen
• ihr kommt
• sie/Sie kommen

So:

• Alle kommen. = correct
• Alle kommt. = incorrect

Even though English everyone often takes a singular verb, German alle takes a plural verb.

Zur is a contraction of zu der.

So:

• zur = zu der

This contraction is very common and usually preferred when it is possible.

Examples:

• zur Schule = zu der Schule
• zur Arbeit = zu der Arbeit
• zur Versammlung = zu der Versammlung

Because the preposition zu normally requires an object, and here that object is der Versammlung in the dative case.

So the full structure is:

• zu + der Versammlung
• contracted to zur Versammlung

German often uses prepositions where English may not think about them as much. In this sentence, kommen zur Versammlung means coming to the meeting/assembly.

It is in the dative case.

That is because zu always takes the dative.

The noun is die Versammlung in the nominative, but after zu it becomes:

• zu der Versammlung
• contracted: zur Versammlung

So:

• nominative: die Versammlung
• dative: der Versammlung

Because it is a noun.

All German nouns are capitalized, no matter where they appear in the sentence.

So:

• die Versammlung
• eine Versammlung
• zur Versammlung

This is one of the big differences from English.

Yes, that is grammatically correct.

But zur Versammlung is more natural in normal German because contractions like zu der → zur are very common.

Using zu der Versammlung may sound more deliberate or slightly emphatic in some contexts, but it is not wrong.

Not exactly.

• kommen focuses on coming, often from the perspective of the destination or the speaker.
• gehen focuses on going.

So both can be possible depending on viewpoint:

• Alle kommen zur Versammlung. = Everyone is coming to the meeting.
• Alle gehen zur Versammlung. = Everyone is going to the meeting.

English often uses come and go differently from German, so this can depend on context.

Often yes, but it can sound a bit more formal or organized than some uses of meeting.

Versammlung can mean:

• assembly
• gathering
• meeting

Depending on context, it might refer to a formal group gathering, a public assembly, or an organized meeting. The exact English word depends on the situation.

The sentence follows normal German main-clause word order:

Alle | kommen | zur Versammlung subject | verb | other information

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

If another element were placed first, the verb would still stay in second position:

• Heute kommen alle zur Versammlung.

So the core pattern is very typical German word order.