[chiharu]

Dear Teacher:

Can you please teach which of the following sentences are correct?

"Among the most satisfying experiences for me as a teacher has been opportunity to work as an assistant helping professors."

"Among the most satisfying experiences for me as a teacher has been an assistant helping professors."

I often read the sentence like "Among the most satisfying experience for me
as a ... has been +ing.."

Is this the fixed sentence or a general way of saying in English?
I think that for most cases, it goes "has + been +ing".
Can it be with "has + been + noun" like "opportunity" or "assistant"?

Thanks

Chiharu