Warning signs
Narrow Bridge sign
The bridge ahead is narrower than the road you are on, though two lanes still fit.
How to recognise it
This sign is a diamond stood on its point in yellow, the warning colour. Yellow diamonds telling you what the road is about to do. They are advisory rather than mandatory, but ignoring them is how people end up in ditches and how examiners end up failing you.
What the test wants you to know
A narrow bridge still carries both directions. A one lane bridge sign is different and means only one vehicle can cross at a time, so the first to arrive goes first.
Practise it
Reading about a sign is not the same as recognising it in half a second with an examiner watching. Every state road signs test on this site shows the sign and asks you to name it, then shows four faces and asks you to pick the right one.
Same family
Right Curve
Left Curve
Cross Road
Side Road
Merge
Lane Ends