“every”后面的名词应为单数。
every
英 ['evrɪ] 美 ['ɛvri]
adj. 每一的，每个的；每隔…的
every time 每次，每当
every one 每个
every single [口语][加强语气]每一个
every other 所有其他的；每隔一个的
every bit 完全；每一点；从头至尾
They cocktailed once every week.
他们每星期喝一次鸡尾酒
Every citizen should uphold the Constitution.
每个公民都应当维护宪法。
We carefully watched every detail of his action.
我们仔细观察了他动作的每个细节。
Little Tom could always answer up to every question.
小汤姆对每个问题往往都能对答如流。