English Translation
He is ashamed of having been idle in his youth.
What’s wrong with “war” rather than “gewesen zu sein”
He is ashamed of having been idle in his youth.
What’s wrong with “war” rather than “gewesen zu sein”
I am not sure what you mean.
In this construction you need the “Infinitiv mit zu”.
You can say
“Er schämt sich dafür, dass er in seiner Jugend untätig war.”
“He is ashamed that he has been idle in his youth.”
However, the above variant with “zu” sounds to me more elegant (just like in English?).
“He is ashamed that he was idle in his youth”
“He is ashamed of having been idle in his youth”
I’d say they’re about equivalent in English, neither one sounds more elegant than the other in my opinion. But you need to pay attention to “ashamed of” versus “ashamed that”, because if you use the wrong verb, it will sound very strange:
“He is ashamed that having been idle in his youth” = incorrect
“He is ashamed of he was idle in his youth” = also incorrect
Very similar thing in German, if you use “dass” to introduce the subordinate clause, then it changes what verb you will use in that clause to form a correct sentence.