Biz misafirleri kapıda karşılıyoruz.

Yes. The ending -uz in karşılıyoruz already shows the subject is we, so biz is not strictly necessary.

Turkish often drops subject pronouns when the verb ending makes the subject clear. So:

Misafirleri kapıda karşılıyoruz.
already means We are welcoming the guests at the door.

Adding biz can give extra emphasis, contrast, or clarity, like:

• We are welcoming the guests.
• As for us, we are welcoming the guests.

So biz is correct, but not required.

In this sentence, misafirleri is:

• misafir = guest
• -ler = plural
• -i = accusative marker

So it means the guests as a specific direct object.

Turkish uses the accusative ending on definite or specific direct objects. English often uses the for this idea, but Turkish does not have a separate word for the.

So:

• misafirleri = the guests / those specific guests

Because Turkish usually does not use articles the way English does.

Instead, definiteness is often shown by context or by grammar. In this sentence, the object misafirleri has the accusative ending -i, which helps show that the guests are specific/known.

Compare the general idea:

• misafir = a guest / guests / guest(s) in a general sense
• misafirleri = the guests / specific guests

So Turkish often expresses what English does with the by using case endings instead.

Because of vowel harmony.

The word misafir has i as its last vowel, and i is a front vowel, so the plural suffix becomes -ler.

• front vowels: e, i, ö, ü → -ler
• back vowels: a, ı, o, u → -lar

So:

• misafir → misafirler

Kapıda means at the door.

It breaks down like this:

• kapı = door
• -da = in / at / on

This is the locative case, used for location.

So:

• evde = at home / in the house
• okulda = at school
• kapıda = at the door

In this sentence, it tells you where the welcoming is happening.

This is because the locative suffix changes depending on the final sound of the noun.

After a voiced sound or a vowel, you usually get:

• -da / -de

After a voiceless consonant, you usually get:

• -ta / -te

Since kapı ends in a vowel, the correct form is:

• kapıda

Compare:

• oda → odada
• sokak → sokakta

It comes from the verb karşılamak, which means to meet, to receive, or to welcome.

The form karşılıyoruz can be analyzed as:

• karşıla- = verb stem
• -ıyor = present continuous
• -uz = we

So:

• karşılıyoruz = we are welcoming / we are meeting

One important thing happens here: when -yor is added, the final vowel of the stem often drops or changes in appearance.

So:

• karşıla- + -ıyor → karşılıyor
• then karşılıyor + uz → karşılıyoruz

This is very common with verbs ending in -a or -e:

• başlamak → başlıyor
• beklemek → bekliyor

The -yor form is usually taught first as the present continuous, so the basic meaning is:

• we are welcoming
• we are meeting

But in real Turkish, -yor can also be used for:

• actions happening now
• actions around the present time
• habits
• planned near-future events

In this sentence, the most natural reading is we are welcoming the guests at the door, but depending on context it could also describe a regular practice, such as at an event or hotel.

It can be any of those, depending on context.

With kapıda meaning at the door, karşılamak strongly suggests:

• to welcome
• to receive
• to meet someone on arrival

So here it is not just casually meeting someone somewhere. It has the sense of going to receive them when they arrive.

That is why welcome the guests at the door is a very natural interpretation.

Not completely, but the verb usually stays at the end in neutral Turkish word order.

This sentence follows a common pattern:

Biz = subject
misafirleri = object
kapıda = location
karşılıyoruz = verb

So the overall structure is close to Subject + Object + Place + Verb.

You could also say:

• Biz kapıda misafirleri karşılıyoruz.

That is still grammatical. The difference is usually about emphasis or what the speaker wants to highlight.

The version you gave sounds natural and straightforward.

Yes, in isolation misafirleri can be ambiguous.

It can sometimes mean:

• the guests as an accusative object
• his/her guests
• in some contexts, their guest(s)

But in this sentence, because it is followed by karşılıyoruz and functions as the direct object, the most natural reading is the guests.

This kind of ambiguity is normal in Turkish, and context usually resolves it quickly.