De zevende afspraak is morgen.

Because afspraak is a de-word in Dutch. In the singular, Dutch nouns take either de or het, and afspraak takes de: de afspraak.

Unfortunately, there is no perfect rule that lets you always guess this, so learners usually memorize the noun together with its article.

No. Afspraak can mean several related things, depending on context:

• appointment
• arrangement
• agreement
• sometimes even date

In this sentence, it most naturally means appointment.

Because zeven means seven, while zevende means seventh.

Dutch, like English, uses a special ordinal form when you are numbering something in order:

• zeven = seven
• zevende = seventh

So de zevende afspraak means the seventh appointment.

Zevende is the Dutch ordinal form of zeven.

Many Dutch ordinals are formed with endings such as -de or -ste. For zeven, the correct ordinal is zevende. So this is just the normal dictionary form for seventh.

In Dutch, ordinals used before a noun normally appear in the -e form. So before afspraak, you say zevende.

That is why de zevende afspraak is correct, and de zevend afspraak is not.

Because Dutch main clauses follow the verb-second rule, often called V2.

In De zevende afspraak is morgen:

• De zevende afspraak is in first position
• is must come in second position
• morgen comes after that

So the word order is normal Dutch main-clause word order.

Yes. Morgen can mean either tomorrow or morning, depending on context.

In this sentence, it clearly means tomorrow.

If you want to say in the morning, Dutch often uses expressions like 's morgens.

Because Dutch uses words like vandaag, gisteren, and morgen directly as time adverbs.

So you say:

• Het is morgen
• Ik kom morgen
• De afspraak is morgen

You do not need a word like on or at before morgen.

Yes, that is also correct.

Dutch lets you move different parts of the sentence to the front for emphasis. If you put morgen first, the verb still has to stay in second position:

• De zevende afspraak is morgen
• Morgen is de zevende afspraak

Both are grammatical, but the emphasis is slightly different.

In a normal full sentence, yes.

De shows that you mean a specific appointment: the seventh appointment. Without the article, zevende afspraak is morgen sounds unnatural in ordinary speech and more like note style, headline style, or shorthand.

Yes, you could, and people would understand it.

But there is a difference in style:

• de zevende afspraak = the normal, standard way to say the seventh appointment
• afspraak nummer zeven = more like appointment number seven

The nummer version can sound a bit more administrative, list-like, or spoken.

A rough guide is:

• zevende ≈ ZAY-vuhn-duh
• afspraak ≈ AHF-spraak

More approximately in IPA:

• zevende = /ˈzeː.vən.də/
• afspraak = /ˈɑf.spraːk/

A few pronunciation notes:

• z in Dutch is like English z
• ee in zevende is a long vowel
• aa in afspraak is also a long vowel
• the stress is on the first syllable of each word: ZEvende AFspraak