Beijing has an extensive public transportation network. Subway and City Rail with high speed trains running at intervals of 3 to 5 minutes are the fastest public transportation in the city. There are more than 60 thousand taxis in the city. Public buses are the cheapest means of transportation which cover the entire city. The starting fare of public buses is 1 Yuan in the city and 2 Yuan in the suburb areas. It is also a good idea to buy a Public Transportation Card which charges a starting fare of 40 cents per trip. You need to pay a deposit of 20 Yuan and prepay a certain amount to use the Public Transportation Card just like any Beijing citizen. When you leave Beijing, just return the Card at any card sale counter and the deposit will be refunded to you. The Public Transportation Card can also be used in Subway and City Rails but no discount on the ticket fares will be given. 1. This passage is talking about Beijing's (46) . 2. (47) and (48) are the fastest public transportation in the city. 3. If you want to go to the suburb areas, you have to pay (49) Yuan. 4. There are (50) taxis in Beijing.