Gregor's father undergoes a transformation in his physical appearance just like his son. Mr. Samsa is forced to go back to work after Gregor's transformation, and ends up working as a bank messenger. He now stands very erect, dressed in a fancy, blue uniform. His eyes look brighter and his hair is combed. With the change in appearance, Mr. Samsa also gains a new sense of authority.
To be detached literally means to be separated or isolated from something. So this word can help to indicate the dead-end and dull aspect of the street.
As an English speaker the advice i give to someone who wants to learn English would be it does take time but it's actually not that hard to learn English you just need to keep practicing and try to talk with the words you know so you can get used to it.
