If you find yourself at a souk and are interested in making a purchase, you might try asking in Arabic how much anything costs by saying “kam yukalif?”
Also helpful is learning the word for "yes", which is “naam”, and the word for "no", which would be “la”. When you are talking to a man and would like to say “please”, you would say “min fadlak", and when you are addressing a lady, you would say "min fadlik". Note the subtle changes when you address a man and a woman.
In the event that you accidentally bump into somebody, you should say "excuse me", which would be “alma derah” or "sorry", which would be “aasef”.
“Thank you” is very commonly used in any language and in Arabic it is “shukran”. You are likely to use this everywhere you go, be it the markets, restaurants, or the luxury resorts in Dubai you are staying at. Although all resort staff like the ones in Anantara The Palm Dubai Resort speak in English, you can always speak a word or two in Arabic and see their surprise.