zhè / zuò / chéng / shì / zài / shàng / shì / jǐu / shí / nián / dài / jìn / rù / le / jīng / jì / fā / zhǎn / de / dǐng / shèng / qī这座城市在上世纪九十年代进入了经济发展的鼎盛期。This city reached the peak of its economic development in the 1990s.