Dìtú shàng de shānmài yòng tūqǐ de xiàntiáo biǎoshì.
The mountain ranges on the map are shown by raised lines.
Tips
memory
The character 凸 is a perfect ideogram - its outline literally bulges upward. Pair it with its opposite 凹 (āo, 'concave', literally a dent in the character's outline) and you have one of Chinese script's most charming visual jokes.
