后车之鉴

1. • lit. warning to the following cart (idiom) don't follow the track of an overturned cart
2. • fig. draw lesson from the failure of one's predecessor
3. • learn from past mistake
4. • once bitten twice shy

Character by character

• 后(hòu)surname Hou
• 车(chē)surname Che
• 之(zhī)(possessive particle, literary equivalent of 的 de)
• 鉴(jiàn)bronze mirror