Illinois Road Signs Practice Test
Sharpen the skill the Written exam (traffic laws and traffic sign identification) leans on most: 25 questions on road sign shapes, colors, and meanings, each explained in plain English. The real SOS Written exam (traffic laws and traffic sign identification) has 35 questions, and you need 28 correct (80%) to pass.
Tap an answer. The explanation opens so you can learn it, then go on. Keyboard: A–D or 1–4 to answer, then Enter or Space.
Question 1 of 25
1. You see a yellow diamond sign showing an arrow that bends left, then right, then left again. What does this sign tell you about the road ahead?
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Correct answer: C. A winding road sign warns of three or more curves in a row, while a single-bend arrow marks just one curve. Knowing the difference helps you hold a safe speed. Think: a wiggly arrow means the wiggles keep coming.
2. A yellow diamond shows a bicycle and the words SHARE THE ROAD. What is it asking you to do?
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Correct answer: B. Share-the-road warnings remind you that bicyclists are legal traffic. Slow, wait for a clear gap, and pass with generous space. The sign exists because drivers otherwise squeeze bikes toward the gutter.
3. Without reading any words, what does a yellow, diamond-shaped sign tell you?
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Correct answer: C. Yellow diamonds are warning signs: they alert you to hazards or changing conditions such as curves, intersections, or merging traffic. They advise rather than order. Shape and color alone should make you lift off the gas.
4. You plan to leave the freeway at exit 12. How will you know which ramp is yours?
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Correct answer: B. Freeway exits carry green guide signs topped with a numbered exit panel, and the number usually matches the nearest milepost. Match the posted number to your planned exit, then move into the exit lane early.
5. At the top of a ramp you see a square sign with a red circle and a white horizontal bar reading DO NOT ENTER. What does it mean?
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Correct answer: A. DO NOT ENTER marks a roadway where traffic flows toward you, such as an exit ramp or one-way street. Entering it risks a head-on crash. If you have already turned in and see WRONG WAY, pull over and turn around safely.
6. 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, not to overtake.
7. A yellow diamond shows two arrows pointing toward each other. What conflict is ahead?
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Correct answer: A. The two-way traffic warning tells you opposing cars will soon share the road, often after a divided or one-way segment. Keep right and expect headlights in the other lane. Two arrows, two directions.
8. A white regulatory sign reads NO TURN ON RED. You have a circular red light and want to go right. What must you do?
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Correct answer: B. NO TURN ON RED cancels the usual after-stop right turn. Wait for green. Cities post this where pedestrians or poor sightlines make a red-light turn dangerous. The sign overrules the general permission.
9. You are driving in a lane with a large white arrow painted on the pavement curving to the right. What does this marking require?
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Correct answer: B. A curved lane-use arrow makes that lane turn-only: follow the arrow or change lanes before the intersection. The arrows sort traffic early so drivers do not swerve at the last second. The pavement is telling you your path.
10. A white sign with a green arrow and the word ONLY is mounted beside a traffic signal. When may you move in that direction?
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Correct answer: B. A signal-mounted green arrow with ONLY ties that movement to the arrow indication. Go that way when the arrow is on and the path is clear; otherwise wait. Arrows assign time as well as direction.
11. A wide white bar is painted across your lane just before an intersection with a stop sign. Where must you stop?
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Correct answer: D. A stop line marks the exact place to stop: bring your vehicle to a halt before the bar, not on or past it. It keeps you clear of crosswalks and cross traffic. The bar is the boundary.
12. 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 lose in a collision with a car. Treat the walking figure as a person already stepping off the curb.
13. 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.
14. You see a red-and-white triangular sign reading YIELD as you approach a traffic circle. What should you do?
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Correct answer: B. A yield sign tells you to slow down, check for traffic with the right-of-way, and stop only when necessary to let it pass. It keeps merges smooth without forcing pointless stops. Think of yield as give way, not a full stop every time.
15. 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.
16. On a dark road you see several black-and-yellow signs, each with a single sideways V pointing to the right, spaced along the roadside. What do they mark?
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Correct answer: B. Chevron alignment signs outline a sharp curve, each arrowhead pointing the direction the road bends. They are placed in a series so your headlights pick up the curve's shape at night. Follow the chevrons like breadcrumbs through the turn.
17. 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.
18. 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.
19. You reach a stop sign at an intersection that has a painted stop line. Where must you bring your vehicle to a complete stop?
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Correct answer: A. At a stop sign you must stop completely before the stop line; with no line, stop before the crosswalk or the intersection edge. Stopping short protects people in the crosswalk. If you need a better view, creep forward only after the full stop.
20. An orange triangle with a red border is mounted on the back of a vehicle ahead. What is that vehicle doing?
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Correct answer: B. The slow-moving-vehicle emblem marks farm and other equipment that usually travels 25 mph or less. Give it a wide berth and pass only when you can see far enough ahead. Orange triangle equals slow vehicle.
21. 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.
22. 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.
23. You are in the right lane when you see a yellow diamond sign showing the right lane narrowing into the left lane. What should you do?
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Correct answer: B. A lane-ends sign warns your lane will disappear, so signal, match the other lane's speed, and merge before the pavement runs out. Drivers in the ending lane must yield to through traffic. Early, smooth merges prevent the last-second squeeze.
24. A diamond-shaped orange sign with black markings is posted ahead of a lane shift. What class of message is that?
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Correct answer: B. Orange diamonds are reserved for temporary traffic-control in work zones. They warn that the road, lanes, or workers ahead are not in their usual place. When the background turns orange, expect cones, narrowed lanes, and people on foot.
25. 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.
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