German Question

[ajaxfetish]

Okay, so I was originally torn up as to which of the following would be the proper hierarchy for German auxiliaries:

1)
Future
Modal
Perfect
Passive

2)
Future
Perfect
Modal
Passive

The new hypothesis is that the order is as follows:

3)
Future
----Modal A
Perfect
----Modal B
Passive

This predicts that the future will always occur higher in the structure than any other auxiliary, and the passive will always occur lower. Modals and perfective auxiliaries may occur in either order relative to each other, but the difference in ordering will imply a difference in meaning. It would still be very unlikely, of course, to find all four types of auxiliaries in the same clause. Looking through Centurio's suggested examples for various combinations of auxiliaries (post #10), everything seems consistent with this.

Spoiler Alert, click show to read: 

Sentence 1: Der Euro muss eingeführt worden sein
----Modal
----Perfect
----Passive

Sentence 2: Der Euro muss eingeführt werden
----Modal
----Passive

Sentence 3: Er sagte, dass der Euro eingeführt worden sein muss / müsse
----Modal
----Perfect
----Passive

Sentence 4: Sie müssen den Euro eingeführt haben
----Modal
----Perfect

Sentence 5: Der Euro wird eingeführt werden müssen
----Future
----Modal
----Passive

Sentence 6: Der Euro muss (bereits) eingeführt gewesen sein
----Modal
----Perfect
----Passive? Another Perfect?
(I'm not yet familiar with this exact construction. I'm used to the plusquamperfect or past perfect involving a preterite form of sein along with a past participle. Here it looks like we've got the infinitive of sein followed by the past participle of sein followed by a past participle. I'm guessing the influence of the modal required the first sein to be in infinitive, making a preterite form impossible, but I couldn't have predicted the result. I'm also unclear as to whether the two stacked sein's mean plusquamperfect, passive, or both. Regardless, it doesn't seem to contradict the above hierarchy)

And for Ser Clegane's mega-sentence with all four auxiliaries: Der Euro wird eingeführt worden sein müssen
----Future
----Modal
----Perfect
----Passive

One other question this raises for me is whether it's ever possible in a German sentence to have two different modals, one in each of the possible modal slots. I suspect it's not, but it would be very intriguing if it is.

Ajax