developing your smart driving skills 34 Obstruction — keep right  or left Obstruction — keep right Obstruction — keep left Pay special attention to object markers — they are mounted on obstructions. Tunnel ahead Object markers Remove sunglasses Snow shed ahead Use headlights ahead Watch for rocks on the  road ahead Opening bridge ahead Watch for deer ahead Hazard or danger ahead  — turn right or left Fire truck entrance ahead Truck crossing ahead Highway or freeway  exit — slow to  advisory speed shown Pavement ends ahead Pedestrian crosswalk  ahead School crosswalk ahead   — this sign is fluorescent  yellow-green School bus stop ahead Cyclists may be on  roadway