“父爱如山”的正确英文翻译是Father's love is as great as a Mountain.
Father's love翻译为：爸爸的爱；
as great as翻译为：和……一样伟大；
a Mountain翻译为：一座山。
as as用法：
as…as…意为“和……一样”，表示同级的比较。使用时要注意第一个as为副词，第二个as为连词。其基本用法为as+ adj./ adv. +as…。例如：
This film is as interesting as that one (is).
这部电影和那部电影一样有趣。
Your pen writes as smoothly as mine (does).
你的钢笔书写起来和我的一样流畅。
