德文為什麼移動動詞(現在完成式 如:fahren 開車,losgehen 走路出發)要用bin動詞(be動詞)?

The auxiliary verb in the verb to be:-(am, is, are, was, were ,be, being, been)
eg:-
Be:-be in the performance of one's duty
------He has been driving
+Have, has
(1)Having driiven/ or Drove
He has driven the car;
He drove the car.
(2)perfect tense:-
eg:-He has driven the car out on the road completed(attributive only) present perfect tense, completed, qualified,=the auxiliary verb--the verb to be.as mentioned before.