Q: I bought my MacBook Pro three in the UK. My charger broke and I'm in Venezuela for the next 5 months. I'm wondering if I buy an American charger will my laptop be okay??

The Apple chargers are all universal on voltage and frequency...they all operate on 100-240 volts.  All that changes is the plug pin configuration.  If you have the UK charger, the plug pin piece slides off, and you can just slide it on the charger you buy so it fits right when you get back to the UK.

vescax,

your MacBook Pro will be fine. You might want to ensure that you have a surge suppressor, though, if brownouts are a problem where you are.

The Apple laptop chargers are: http://support.apple.com/kb/HT2346 and if you look at the right side image of the AC duckbill piece you will see what I mean about removable plug piece...that one pictured is for the US plug, your UK plug just has different pins.