人山人海：有人直译为：People mountain people sea. 这就是"中国英文"，老外很难理解。他们指"人多"时，通常只说："There is a large crowd of people."如果看到电影院门前大排长龙，也只说："There is (was) a long movie line."
不过在诗词用语（poetic expression）裏，老外也有使用："a (the) sea of faces"，颇有咱的"人山人海"的味道。例如：Looking out upon the sea of faces, Mr. A delivered a touching speech.（望著一片人山人海的听众，A先生发表一篇动人的演说。）Standing at his podium, President Clinton saw a sea of faces waving at him.（克林顿总统站在讲台上看到人山人海的人群挥手向他致意。）。
可见，说话者通常要在台上或高处，才有"人海"的感觉。因此，可以说："I saw a sea of faces from the top of the building. "但在平地的人群中，就不说："I saw the sea of faces."也不说："There is a sea of faces."只说："I saw a large crowd of people."
reference:
http://tw.myblog.yahoo.com/hansen-green