South Dakota Road Signs Practice Test
Sharpen the skill the Knowledge Test leans on most: 25 questions on road sign shapes, colors, and meanings, each explained in plain English. You need 80% correct to pass the real DPS Knowledge Test.
Question 1 of 25
1. In a work zone, an orange sign warns of a flagger ahead. The flagger signals you to stop, even though the traffic light beyond is green. What should you do?
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Correct answer: C. Flaggers control traffic through work zones, and you must obey their directions even when they conflict with posted signs or signals. They can see hazards you cannot. Remember: in a work zone, the person outranks the light.
2. A yellow diamond sign shows a side lane curving in to join the main road ahead. You are on the main road. What does the sign mean?
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Correct answer: C. A merge sign warns that another roadway joins yours ahead. Entering drivers must yield, but you should adjust your speed or change lanes when safe to open a gap. Merging works best when both drivers cooperate like a zipper.
3. You pass a round yellow sign marked with a large black X and the letters R R. What is it telling you?
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Correct answer: A. The round yellow RXR sign is the advance warning for a railroad crossing, posted well before the tracks. It gives you time to slow, quiet distractions, and scan for trains. Round and yellow means railroad ahead, not at, the sign.
4. Ahead of a raised concrete median you see a white sign reading KEEP RIGHT with an arrow curving to the right. What should you do?
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Correct answer: A. KEEP RIGHT tells you the roadway splits around an island, median, or obstruction, and all traffic must pass on the right side. Passing left would put you into oncoming lanes. Follow the arrow around the obstacle, then continue straight.
5. On a multilane highway, white lines separate the lanes. What does the white color tell you about the traffic around you?
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Correct answer: B. White lines divide lanes of traffic that flow the same way, while yellow divides opposing flows. Reading line color at a glance tells you instantly where oncoming cars can be. White means with you, yellow means toward you.
6. A yellow diamond sign shows a car with wavy skid marks trailing behind its tires. When does this warning matter most?
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Correct answer: D. The skidding-car sign warns that the road ahead becomes slippery when wet, so slow down and avoid sudden braking or sharp steering in rain, snow, or ice. The first minutes of rain are often the slickest, as water lifts oil off the pavement.
7. An orange sign with a black arrow reads DETOUR. What is this sign telling you?
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Correct answer: A. Detour signs guide you along a temporary route when the normal road is closed, often for construction or an emergency. Keep following the arrows until the detour ends, and the route will return you to your original road.
8. You stop at a red light planning to turn right, and a white sign beside the signal reads NO TURN ON RED. What does the sign change?
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Correct answer: A. Many places allow a right turn on red after a complete stop, but a NO TURN ON RED sign removes that option. It appears where crosswalks or sight lines make red-light turns risky. When posted, red simply means wait.
9. Two solid yellow lines run down the center of the road. What do they prohibit?
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Correct answer: D. Double solid yellow lines ban passing for traffic in both directions, because sight distance or traffic makes passing unsafe there. Crossing is generally allowed only to turn into a driveway or side road, never to overtake.
10. On a two-lane road, the center line nearest your lane is broken yellow, while the line on the far side is solid yellow. When may you cross it to pass?
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Correct answer: C. A broken yellow line on your side means passing is permitted from your direction, but only when oncoming traffic is far enough away to pass safely. Broken means you may cross; solid means stay put.
11. You are driving past a school crossing just as classes let out. What must you be prepared to do?
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Correct answer: C. Near school crossings you must slow to any posted school speed and stop whenever children or crossing guards are in the crosswalk. Kids are small, quick, and unpredictable, so extra caution is required. Expect the unexpected wherever students gather.
12. Which shape is used only for yield signs, so you can recognize the sign even when you cannot read its face?
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Correct answer: D. Only yield signs use the downward-pointing triangle, just as only stop signs use the octagon. Unique shapes let drivers react from the outline alone in fog or darkness. Picture the point aiming down, telling you to back off and give way.
13. Only one road sign is shaped like a sideways pennant, a triangle with its point aimed to the right. Which sign is it?
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Correct answer: A. The sideways yellow pennant is used for one message only: NO PASSING ZONE. It stands on the left side of the road where passing begins to be unsafe. One shape, one meaning makes it instantly recognizable.
14. A center lane is bordered on each side by a solid yellow line with a broken yellow line inside it, and white left-turn arrows are painted for both directions. How may you use this lane?
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Correct answer: A. A two-way left-turn lane is shared by both directions for left turns only. Enter just before your turn, watch for opposing drivers using the same lane, and never travel or pass in it. Turn, do not cruise.
15. A yellow diamond sign ahead shows a plus symbol, like a small cross. What is this sign warning you about?
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Correct answer: A. The crossroad symbol warns that a full intersection is ahead, so vehicles may pull out or turn from the left or right. Slow down and scan both directions. Picture the plus sign as two roads meeting.
16. Orange signs, cones, and barrels suddenly appear along the highway. What does the color orange always tell you?
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Correct answer: B. Orange is reserved for temporary traffic control, meaning construction and maintenance zones. Workers, machines, and lane shifts may appear with little warning, so slow down and stay alert. When you see orange, think people at work.
17. A freeway lane is marked with white diamond symbols, and a sign says the lane is for high-occupancy vehicles (HOV 2+). Who may drive in it during the posted hours?
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Correct answer: B. Diamond-marked HOV lanes are reserved for vehicles meeting the posted occupancy, like two or more people in an HOV 2+ lane. Rewarding shared rides moves more people in fewer cars. The diamond means special rules, so read the sign before entering.
18. A solid white line, instead of a broken one, separates your lane from the next lane going the same way. What is it telling you?
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Correct answer: A. A solid white line between same-direction lanes discourages lane changes, and it appears where drifting is risky, such as near intersections and ramps. The firmer the line looks, the firmer the message: hold your lane.
19. You are driving on a road with few traffic lights when you see a yellow diamond sign showing a traffic signal symbol. Why is this sign posted, and how should you respond?
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Correct answer: B. Signal-ahead warnings are posted where a traffic light may surprise drivers, such as after a long stretch without one or where a hill blocks the view. Ease off the gas early so a sudden red light cannot catch you.
20. A white vertical rectangle reads SPEED LIMIT 55. What does that number legally mean?
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Correct answer: C. A white rectangular speed limit sign is a regulatory sign, so the number is the maximum lawful speed in ideal conditions. Rain, fog, or heavy traffic can make even that speed illegal. Treat the posted number as a ceiling, never a target.
21. You see a five-sided sign shaped like a schoolhouse outline, in fluorescent yellow-green, showing two walking figures. What does the pentagon shape identify?
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Correct answer: D. The pentagon shape is reserved for school signs, warning of a school zone or crossing where children may be walking. The fluorescent yellow-green color grabs attention near schools. Think of the five-sided shape as a little schoolhouse to remember it.
22. On a highway you pass a white regulatory sign reading MINIMUM SPEED 40. Why is that sign posted?
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Correct answer: D. A minimum speed sign requires you to travel at least the posted speed when conditions allow. Highways post it because vehicles moving far below the flow cause rear-end and lane-change crashes. Too slow can be as dangerous as too fast.
23. A yellow diamond-shaped sign ahead shows a black walking figure. As you approach the marked crossing, what is the required response?
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Correct answer: B. A pedestrian crossing warning sign means people may be entering the roadway ahead, so reduce speed and prepare to stop. Pedestrians always lose in a collision with a car. Treat the walking figure as a person already stepping off the curb.
24. On a rural road at dusk you pass a yellow diamond sign showing a leaping deer. What is the proper response?
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Correct answer: A. A deer crossing sign marks a stretch where animals often enter the road, so slow down and watch the shoulders, particularly around dawn and dusk. Deer travel in groups, so one crossing usually means more are coming. Where there's one, expect another.
25. At a railroad crossing you see a white X-shaped sign reading RAILROAD CROSSING, with no gates or flashing signals. How should you treat it?
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Correct answer: B. The crossbuck is a regulatory sign that legally works like a yield sign at the tracks. Trains cannot swerve or stop quickly, so you must give way every time. At passive crossings, your eyes and ears are the only warning system.
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