Vehicles are allowed to pass right when the vehicle in front turns left + tram vehicles running in the middle of the road + special-use vehicles cannot pass left.
Answer 3 is incorrect because of enough space It is not safe to pass a vehicle.
When the vehicle ahead has a signal to turn left or is turning left; when the tram is running in the middle of the road.
When a special-use vehicle is working on the road and cannot pass on the left.