You can get by pretty well with English alone, but a bit of French or Arabic can definitely be advantageous.
The French, I’m sure, can be had in many places. Here’s some basic Arabic that might come in handy:
Keef alhaal? = How are you?
Hamdallah = By the grace of God (reply to above)
Shukran = Thank you
Kem hada = How much is this
And last but not the least, the single most important word you need as a tourist: 'la’ – which, of course, means ‘no’!