Concerns or is concerned

[hnkien]

Hi all and Erin,

You just corrected this sentence long time ago:

Petrography concerns primarily with the detailed description and class fication of rocks where as petrology deals primarily with rock formation.

You corrected:

concerns ==> is concerned

We need passive voice here.

But what I am confused is why concerns ==> is concerned

whereas

deals =/=> is dealt

I think the verb concern and deal here have the same meaning as well as grammar structure.

Any ideas?

[Erin]

The questions we most miss on the TOEFL are the ones that are related to meaning:

Sophia's actions concern me.

This means that Sophia's actions make me worried. "concern" with this meaning is transitive; "me" is the object.

Petrography concerns...

does NOT have the same meaning; "Petrography" does NOT make somebody worried. Furthermore, there's no object.

Moral of the story? With this meaning, we need passive voice.

[hnkien]

Thank you.
I got it.

[Erin]

Awesome!