How can I reload the Beijing Smart Card and can the staff at the Beijing metro station understand my English?

Over 170 designated points have been set in Beijing for users to rent and reload the card. These points are located at the ticket offices of all Beijing metro stations (05:30~23:00), some bus stations, supermarkets (e.g, Jingkelong Convenience Stores, Lianhua Quick, Good Neighbor Supermarket) and Post Offices (09:00~17:00). You can see the specific information on the above content.
When you use it on the bus, it will show you the balance and remind you to reload it before it finish.
Well, some of the staff may understand you in English. Do not worry much about it.