chapter 3 — signs, signals and road markings Warning signs Most warning signs are yellow and diamond‑shaped. They warn of possible hazards ahead.  33 Stop sign ahead Roundabout ahead Signal lights ahead Signal lights ahead — prepare to stop  when lights are flashing Steep hill ahead — slow down Bump or rough road  ahead Narrow structure ahead  — often a bridge Road merges with  another road —  added lane to the  right ahead Right lane ends ahead  Divided highway ends  ahead — keep right Two-way traffic ahead Road narrows ahead Sharp curve ahead  — slow to advisory  speed shown Curve ahead —  slow down Merging traffic  ahead Winding road  ahead Hidden side road  ahead Road may be slippery ahead 