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Illinois CDL — General Knowledge practice

Road Signs

Learn the shapes, colors, and meanings of regulatory, warning, and guide signs — from stop and yield to construction and school-zone signs.

Questions reviewed against the official Illinois driver handbook · July 7, 2026

4 questions · pass with 3 correct. You get instant feedback and an explanation after every answer.

Study questions with answers

4 sample Road Signs questions with the correct answer, a short explanation, and the official handbook reference. Read through them, then take the quiz above.

  1. 1. A placarded hazardous-materials vehicle must display at least how many placards?

    Correct answer: Four identical placards

    A placarded load must show at least four identical placards, one readable from each of the four directions around the vehicle.

    Source: Illinois CDL Guide — Sec. 2.24, Hazardous Materials

  2. 2. At a railroad crossing, what does a sign beneath the crossbuck showing a number indicate?

    Correct answer: The number of tracks at the crossing

    When the road crosses more than one set of tracks, a small sign under the crossbuck states how many tracks there are, so you know to check each one before proceeding.

    Source: Illinois CDL Guide — Sec. 2.15, Railroad Crossings

  3. 3. What does a round, black-on-yellow sign placed ahead of a railroad crossing mean?

    Correct answer: A railroad crossing is ahead — prepare to stop

    The round yellow advance warning sign tells you a railroad crossing is ahead. Slow down, look and listen for a train, and be ready to stop at the tracks.

    Source: Illinois CDL Guide — Sec. 2.15, Railroad Crossings

  4. 4. What shape and orientation must a hazardous-materials placard have?

    Correct answer: A diamond set on a point

    A placard is set on a point in a diamond shape and must measure no less than 10 3/4 inches on each side, readable from every direction around the vehicle.

    Source: Illinois CDL Guide — Sec. 2.24, Hazardous Materials

Practice Road Signs in another state

Every Illinois question is written from the official Illinois driver handbook and checked against its current edition. DMV Test Free is a free, independent study resource — not affiliated with any DMV or government agency. About DMV Test Free