Eyes are used for seeing.
for seeing
seeing.
it is used as a seeing
They are used for seeing.
seeing.....
eyes
Mostly they are used for seeing.
"Your seeing things"
Bifocals are used for distance seeing or at close up seeing.
by taking flash. [bulb for seeing this answer]
people get used to seeing it and starts to ignore it.
It could be to 'focus' on something