Hi, how do i get from Beijing Airport to South Train Station? Train or Taxi?

You mean Capital Airport, right? You can take Airport Express train from PEK to Dongzhimen Station, and change to metro line 2 to Xuanwumen Station. Then, change to metro line 4 to South Railway Station. The fare totals CNY 30, and the trip takes 50 to 60 minutes.

If by taxi, the fare may be CNY 120 to 130. The trip takes 50 to 60 minutes.

Or, you can take shuttle bus line 10 to South Railway Station from PEK. The fare is CNY 24, and duration is about 1 hour.