战国时期 (Zhànguó shíqī) is a noun phrase meaning "the Warring States period," a major era in Chinese history (475–221 BC). It combines 战国 (Warring States) with 时期 (period/era). This term is standard in historical writing and storytelling.
战国时期,各国之间经常发生战争。
zhànguó shíqī, gè guó zhījiān jīngcháng fāshēng zhànzhēng.
During the Warring States period, wars frequently broke out between the states.
很多成语故事都来自战国时期。
hěn duō chéngyǔ gùshì dōu láizì zhànguó shíqī.
Many idiom stories come from the Warring States period.
战国时期的文化发展非常丰富。
zhànguó shíqī de wénhuà fāzhǎn fēicháng fēngfù.
The cultural development during the Warring States period was very rich.