Would you please explain

[zaffar]

Dear teacher,
The answer to the last post made me very anxious because it is contrary to what i have learned in a book "A high school english grammar and composition" by "Pc Wren and Martin." This book is widely acclaimed book on english grammar and is being published since 1930. This book says that " The participles have also passive forms, for example
1) The participle of "loving" is "being loved." (this is simple form)
2) The participle of having loved is " having been loved." ( this is passive of the perfect participle)

But, while replying to my post the teacher said that it is wrong to say
"The true nature of the english language having been understood(by me), I don't have this problem anymore. The above phrase is aboslute. I am worried because i have been using the same structure during essay answers in my tests and exams. please reply
thanks in advance,
Zaffar.

[Tdol]

You can't put all sentences into the passive naturally. when talking about yourself, the focus is generally on yourself, so which sounds better?:
I did it.
It was done by me.

IMO, the passive has to be used for a reason, and that sentence doesn't work. A form may exist, but that doesn't mean it can be used. The problem here is the 'by me', not the concept of 'having been understood'.