每四年一届英语

once in four years 或者 every four years 都可以所以是：hold once in four years hold every four years

四年一次：once four years

四年一次每四年一次 once every four years ; Every four year；once four yearsquadrennial英 [kwɒ'drenɪəl] 美 [kwɑd'rɛnɪəl] 跟读 口语练习adj. 每四年一次的；连续四年的n. 第四周年纪念

每四年一次: once every four year 例句：在美国，总统选举每四年一次。In the United States , presidential elections are held once every four year.