What is the meaning of the signs?

1. Correct answer: Directional, above the lanes before an interchange on an Inter –urban road or a Motorway (Freeway).
2. Directional, to a central area or town.
3. Directional, to lanes before a junction, and positioned on the left.
4. Directional to lanes before a junction and placed on the right.

WhyBlue and green boards with downward arrows over the lanes show which lane leads where before an interchange. They are placed on inter-urban roads and motorways.