Retina MacBook Air keyboard question

[mrgreeneyes]

I noticed on my keyboard many of the keys have a smudges on them almost like they are worn down from being used.
could it be possible or do the keys just need a good wipe down?

what can I use to clean the keyboard? Just a damp cloth?

im not near my macbook at the moment otherwise I would have posted a few photos.

 

[StoneJack]

no usually you can't wipe them out. It is natural worn out, not something oily you can clean out.

 

[mrgreeneyes]

no usually you can't wipe them out. It is natural worn out, not something oily you can clean out.

Is there any way i can replace they keys?

 

[MBAir2010]

replacing keys on a MacBook is kinda easy
knowing what style they are is involved
first i would try using rubbing alcohol on a q-tip
then swirling the key that needs cleaning.
if that does not work, find out if you have a Magic, Butterfly or "other" keyboard.
since amazon and eBay took over the parts department on our planet,
a quick search will get you the correct replacement keys.
unless there is a  repair shop near by that might have extra keys.

I hope this helped!