"Um...zu" is a construction that translates to "in order...to". It is build by a main clause and a subordinate clause that starts with "um" and ends with "zu + infinitive": Janusz spielt Gitarre, um Geld zu verdienen. Janusz plays guitar in order to earn money. One reason that this takes some practice for German learners is that in English you could simply say: "Janusz plays guitar to earn money." while in German you can not shorten the phrase, you will always have to use "um" and "zu". Another thing to keep in mind is that separable verbs put the "zu" between the verb prefix and the stem. Ich gehe in die Stadt um einzukaufen. (Infinitive: einkaufen) I'm going into town to do some shopping.