What does two-way fast lane mean?

[GemmaRose]

The meaning of two-way fast lane is as follows: 1. The yellow dotted line in the center of a two-way two-lane road is used to separate opposing traffic flows. 2. It is generally set on the center line of the roadway, but not necessarily on the geometric center line of the road. Vehicles are allowed to cross the line or turn left when safety is ensured. 3. For two-way roads where the pavement width can accommodate two motor vehicle lanes, a yellow center dotted line should be marked; it is used to instruct drivers to keep to the right, stay in their respective lanes, and drive in designated directions. 4. Each motor vehicle lane on a two-way two-lane highway is 3 meters wide; there is no unified standard for the central median, which should be adapted to local conditions.