everywhere可用作副词、代词和连词，所以它可以用作表语、主语、宾语和引导状语从句。现分别回答如下：

问题一：everywhere可用作表语吗？

回答：可以。everywhere用作表语，表示某种情况很普遍。如：

Trash is everywhere; what a sight! 到处都是垃圾，真煞风景！

Clothes were everywhere; hanging out of drawers, strewn across the floor, even spilling from the wastepaper basket. 到处都是衣服：挂在抽屉上、扔在地上、甚至堆在废纸篓里。

问题二：everywhere可用作主语和宾语吗？

回答：可以。everywhere用作主语时，具有名词的特点。如：

Everywhere seemed to be quiet. 到处显得很安静。

We must clean the house—everywhere looks so dirty. 我们得打扫房子，到处都这么脏。

everywhere有时也用作宾语时，最常见的是用作介词from宾语。如：

People come here from everywhere to see these lights. 人们从四面八方来到这里看这些灯。

They heard from everywhere the lovely clear voices of women singing. 他们听见到处传来女子甜美清晰的歌声。

问题三：everywhere可引导状语从句吗？

回答：可以。

Everywhere I go, I find the same thing. 我到哪儿都发现同样的情况。

Everywhere they appeared there were ovations. 他们所到之处大家都鼓掌。

Everywhere I went in London, people kept remarking on the strange weather. 在伦敦，无论我走到哪里，都有人在不停地议论那儿的奇异天气。