there is one quest, after doing a certain quest in the first town[might be after you get a second profession], your primary class instructor will have a quest for you. You get most of the times two more skills[one for your classes each] or one on certain parts of the quest. Basically, you get stuck going through training to learn where your classes work [like pulling or killing kiters] and where they don't[like assassins having agroed on them selves too much]
give you a good example:
one of the parts for assassins are defencive skills, like a blind skill after you hit a lead attack and off hand attack [you can still use a dual hand after this skill too

]. Your character talks to instructor ng after he gives you the skills and tell him you want to go to the dojo. Here, you have to last for 2 minutes with 2 warriorish guys on you, you can stop them by hiting them down to 1/4 or so health[do that to both and the timer stops]
and you get 50 gold per completed part so, just getting the skills and leaving is alright.. but it's so easy and you'll get at least a total of 300 gold in the end