Word order when there are three verbs in a row without "dass" [duplicate]

Question

I have read this link:

Word order with modal verbs in complex tenses

and I understand the word order fine when there is dass forming a Nebensatz and thus creating three verbs in a row, for example:

Ich weiss, dass ich dich hätte anrufen sollen.

However the following sentence structure confuses me in regards to the word order of the last three verbs:

Tina wird auch eingeladen werden müssen.

In English, this would be Tina will also have to be invited.

Why is the word order werden müssen, and not müssen werden?

Answer 1

Generally, what happens is the second to last move as described here.

All that missing is the fact why "werden müssen" and not "müssen werden"

The basic sentence is:

Tina lädt mich ein.

Now we can introduce a modal, a tense or a passive

Tina muss mich einladen.

Tina wird mich einladen.

Ich werde von Tina eingeladen.

What matters is, in which order the new verbs are introduced. And that's where you get your answer... you can add a modal on top of a passive but not the other way around. Because passive of a modal verb makes no sense.

Tina wird eingeladen. ... passive

Tina muss eingeladen werden .... modal - passive

Tina muss mich einladen. ... modal -

Ich werde von Tina eigeladen gemusst. ... nope, that doesn't make sense.

So for your original sentence the order was like this.

Tina wird eingeladen ... passive

Adding in a modal

Tina muss eingeladen werden.

Adding future

Tina wird eingeladen werden müssen.

Answer 2

I cannot give you any specific grammar rules, but maybe I can clarify the structure and some general principles. In German as in English, main clauses have Subject–verb–object order.

I hear the rain.

Ich höre den Regen.

However, in German the object comes before the verb in many (all?) other contexts:

What do you like to do? — To hear the rain.

Was tust Du gerne? — Den Regen hören.

Now we have this sentence:

Tina will                   .
          have to
                  be 
                     invited

The verb of each line refers to everything below it. Have to what? Be invited. (Not the best English, I know.)

This is the same sentence in German:

Tina wird                         .
                            müssen
                     werden
          eingeladen

The verb of the main clause comes before its object, all other verbs come after their objects.

While I think that this should already clarify things, how would a German parse the following sentence that you suggest?

* Tina wird eingeladen müssen werden.

Well, according to the above, that would have to be understood like that:

Tina wird                         .
                            werden
                     müssen
          eingeladen

This would be like

* Tina will will must invited.

or

* Tina will be must invited.

So, should you ever want to express that, you now know how to do it ;)