Wenn der Vertrag befristet ist, suche ich lieber eine andere Wohnung.

Because wenn introduces a subordinate clause in German, and in subordinate clauses the conjugated verb usually goes to the end.

So:

• Wenn = if / when
• der Vertrag = the contract
• befristet ist = is fixed-term / is temporary

This is a very common German pattern:

• Wenn ich Zeit habe, ...
• Weil er krank ist, ...
• Dass sie hier wohnt, ...

In all of these, the finite verb goes to the end of the subordinate clause.

Because the sentence begins with a subordinate clause:

• Wenn der Vertrag befristet ist, ...

After that whole clause, German uses verb-second word order in the main clause. The subordinate clause counts as the first element, so the verb must come next:

• Wenn der Vertrag befristet ist, suche ich lieber eine andere Wohnung.

Structure:

1. Wenn der Vertrag befristet ist = first element
2. suche = verb in second position
3. ich = subject

This is why suche ich is correct here, not ich suche.

Compare:

• Ich suche lieber eine andere Wohnung.
• Wenn der Vertrag befristet ist, suche ich lieber eine andere Wohnung.

Befristet means limited in time, fixed-term, or temporary.

With Vertrag, it usually means the contract has an end date and does not continue indefinitely.

Common contrast:

• befristeter Vertrag = fixed-term contract
• unbefristeter Vertrag = permanent / open-ended contract

So Der Vertrag ist befristet means the contract is time-limited.

Because der Vertrag is the subject of the clause der Vertrag ... ist befristet.

The subject is in the nominative case, and Vertrag is a masculine noun:

• nominative: der Vertrag
• accusative: den Vertrag
• dative: dem Vertrag
• genitive: des Vertrags

Here, the contract is the thing that is fixed-term, so it must be nominative:

• der Vertrag ist befristet

If it were the object of a verb, then you might see den Vertrag instead.

Lieber means rather or preferably here.

So:

• Ich suche lieber eine andere Wohnung = I’d rather look for another apartment / I prefer to look for another apartment

It expresses preference.

Related forms:

• gern = gladly / like doing
• lieber = rather / prefer
• am liebsten = most preferably / like best

Examples:

• Ich wohne gern hier. = I like living here.
• Ich wohne lieber allein. = I’d rather live alone.
• Am liebsten wohne ich in der Stadt. = I prefer living in the city most of all.

This is about article + adjective endings.

The noun is Wohnung, which is feminine. It is the direct object of suche, so it is in the accusative case. For feminine nouns, nominative and accusative both use eine.

Then the adjective andere takes the ending -e after eine.

So:

• eine = feminine accusative article
• andere = adjective agreeing with Wohnung
• Wohnung = feminine noun

Together: eine andere Wohnung = another apartment

Compare:

• ein anderer Vertrag = another contract (masculine nominative)
• einen anderen Vertrag = another contract (masculine accusative)
• eine andere Wohnung = another apartment (feminine nominative/accusative)
• ein anderes Haus = another house (neuter nominative/accusative)

Because in German, a subordinate clause is normally separated from the main clause by a comma.

So:

• Wenn der Vertrag befristet ist, suche ich lieber eine andere Wohnung.

This comma is required in standard German.

You will see this with many conjunctions that introduce subordinate clauses, such as:

• wenn
• weil
• dass
• obwohl
• als

Examples:

• Weil ich müde bin, gehe ich nach Hause.
• Wenn es regnet, bleibe ich drinnen.

Wenn can mean both if and when, depending on context.

In this sentence, it most naturally means if:

• Wenn der Vertrag befristet ist, ... = If the contract is fixed-term, ...

Why? Because the sentence describes a condition.

Very broadly:

• wenn = if / whenever / when
• als = when, for a single event in the past

Examples:

• Wenn ich Zeit habe, komme ich. = If I have time, I’ll come.
• Wenn ich in Berlin bin, besuche ich sie. = When/whenever I’m in Berlin, I visit her.
• Als ich in Berlin war, besuchte ich sie. = When I was in Berlin, I visited her.

So here, wenn is conditional: if.

Yes, you could. Falls also means if, and it can sound a bit more explicitly conditional or slightly more formal/cautious.

Compare:

• Wenn der Vertrag befristet ist, suche ich lieber eine andere Wohnung.
• Falls der Vertrag befristet ist, suche ich lieber eine andere Wohnung.

Both are correct.

Very roughly:

• wenn = neutral, very common
• falls = if it turns out that / in case

In everyday speech, wenn is often the most natural choice.

German often uses the present tense to talk about the future, especially when the future meaning is clear from context.

So:

• suche ich lieber eine andere Wohnung

can naturally mean:

• I’d rather look for another apartment
• I’ll rather look for another apartment
• I’d prefer to look for another apartment

German does have a future form:

• werde ich lieber eine andere Wohnung suchen

But that is often unnecessary. The simple present is much more common in ordinary speech.

Yes, that is grammatically correct.

Both are possible:

• Wenn der Vertrag befristet ist, suche ich lieber eine andere Wohnung.
• Ich suche lieber eine andere Wohnung, wenn der Vertrag befristet ist.

The difference is mainly one of focus and style:

• Starting with Wenn ... foregrounds the condition.
• Starting with Ich suche ... foregrounds the action/result.

In the first version, the speaker emphasizes the condition first:

• If the contract is fixed-term, I’d rather look for another apartment.

In the second, the speaker first states what they do, then adds the condition.

In most cases, yes. Wohnung is the standard German word for apartment or flat.

A few related words:

• die Wohnung = apartment / flat
• das Haus = house
• das Zimmer = room
• die Unterkunft = accommodation
• die Mietwohnung = rental apartment

In this sentence, eine andere Wohnung is exactly the natural phrase for another apartment.

It follows a very common German pattern:

Subordinate clause + comma + main clause

More specifically:

• Wenn der Vertrag befristet ist, = subordinate clause
• suche ich lieber eine andere Wohnung. = main clause

The key rules are:

1. In the subordinate clause, the verb goes to the end.

   • ... befristet ist

2. In the main clause, the verb stays in second position.

   • suche ich ...

This is one of the most important German sentence structures to master, because it appears constantly in real German.