What is the difference ?

又是美式,英式英語的老問題.香港人自細就接受英式英語教育,對美式英語一無所知,簡直是落後于人,與時代脫節.every single day 是正統的美語,每個美國人都是這樣講的.希拉莉和奧巴馬的演講詞幾乎每一次都用上every single day,得閒看多d英文台,英文台的劇集,新聞用的英文9成9係美式英語. everyb single day的意思就是每一天.

every single day只不過係會嚟強調每一日都會去做
同英式美式英語 無乜關係架噃
希拉莉 同奧巴馬成日用只不過佢地用嘅性質係需要去強調佢地講嘅野 因為當你話every single day 你所講嘅野係比較有說服力，唔係因為佢地係美國人先會咁講
發問者起碼知道，聽過呢一句說話，英文每一日都會變，唔知或者未知無乜大不了，你都唔會乜都知la.

"everyday "is an adjective.
e.g.Death was an everyday occurrence during the Civil War.
"Every day " should be used for the above sentence.
agree with the 1st answer that "single" is redundant and should be omitted.