Fix grammaticality: I have studied chemistry at Osaka university for 6 years, and now work in cosmetic company as a researcher.
The following is a list of the most important words in the,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
I have been working in the field of chemistry for 6 years.

I have been working in the field of chemistry for 6 years.

I have been working in the field of chemistry for 6 years.

I have been working in the field of chemistry for 6 years.

I have been working in the field of chemistry for 6 years.

I have been working in the field of chemistry for 6 years.

I have been working