It is probably worth doing a lesson before you go to phase 3. I did my phase 3 last week and I failed. I have only had one introductory lesson a couple of years ago and they asked me why I had not pursued my flying career more as I am now 24 with only 1 hours experience. I think you need to come up with a very good answer to this as it stumped me a bit.
Other questions which they asked me regarding the industry are:
What is the maximum number of hours an airline pilot can fly each year?
Can you tell me about 3 recent news stories within the industry? - Do some reading on this i.e. Flight International.
Also learn the typical duties of a pilot, what they do before take off etc.