This road sign means: Question This road sign means: Answers When pavement is wet, reduce your speed. The road ahead winds in a series of turns or curves. Traffic increases ahead. Explanation Warning signs are usually yellow with black markings. This sign warns drivers that the roadway will be slippery when wet and they should reduce their speed accordingly. This questions appears in the following tests: Delaware Motorcycle Practice Test 8 Idaho Motorcycle Practice Test 77 Illinois Motorcycle Practice Test 14 Wisconsin Motorcycle Practice Test 45 Wyoming Motorcycle Practice Test 32