Answer:
I believe it means that once you rech your fullest potential, you can make the imposible, posible.
It could also mean that who you are now, you used to think was impossible.
Explanation:
Theses are the two posible meaning I came up with by looking at it two different ways.
If you are trying to correct it, the answer would be...
While visiting Washington, D.C., we went to the Lincoln Memorial and the Vietnam Memorial.
If you want something I suggest about manatees?
Man vs. Nature
The natural forces of the Earth are acting against him.