zhè / gè / guó / jiā / céng / jīng / shí / xíng / suǒ / guó / zhèng / cè / jìn / zhǐ / duì / wài / mào / yì这个国家曾经实行锁国政策,禁止对外贸易。This country once adopted an isolationist policy and prohibited foreign trade.