Why do I want to be a geologist?

Hi!!
Today in my English class I spoke on the topic of:
Why do I want to be a geologist?
My answer was because i believe that geology is very interesting, and that each practice of  fieldwork becomes a unique experience.

Please correct my mistakes (:

-Is it pyrite in that picture?

¿wWhy I want to be a geologist?

hi!!
today in my english class speak of we discussed 
¿why I want to be a geologist?
and my answer is because i believe what the geology is much very interesting, and that each practice of what is done conducting research in the field becomes is a unique experience.

please correct my mistakes (:

Great job and good luck!

Why I want to be a geologist. 

Hello!
The topic of my english class today was why I want to be a geologist.  
I want to be a geologist because I believe what the geology is very interesting, and that each practice of what is done in the field becomes a unique experience.

Please correct my mistakes.

Best of luck with your future carreer! 

Leslie