Privet.
How do you say in Russia:
1. I have an expertise on (the analysis of) International Trade.
2. I have an expertise on (the portfolio management of) High Net Worth Individuals.
3. He is an expert on genetics.
4. He is specialized on Chinese Customers.
Also can someone please tell me how you can say in Russia: I ranked first in the university/class/contest (i.e. I had the highest mark).