before ten years与ten years before含义一样吗?

问题描述:

before ten years与ten years before含义一样吗?
造句

before ten years,是before ten years from now的简单说法.
ten years before是当时那个时间点之前的10年
比如They'd arrived there ten years before cops found them in 1980.
他们1970年就到了