As far as the eye can see:
For a long distance until something is so far away and small, it cannot be seen any more.
“As far as the eye can see” 的意思是 “某事物填满了视野，直到看不见”，可以用来描述事物 “一望无际” 或 “广袤无边”。
例句
From the top of the mountain, there were lakes and valleys for as far as the eye can see.
从山顶眺望，眼到之处遍是湖泊和山谷。
I own all the land from here to as far as the eye can see.
目光所及之处都是我拥有的土地。
There is clear sky as far as the eye can see.
一眼望去，尽是晴朗的天空。
