How satisfied are you with Rocket?
How likely are you to buy again?
Are you happy with the price?
Would you recommend it to a friend?
How was the customer service?
The progressive learning of key phrases is an excellent way to build up a core of knowledge that can be applied to various scenarios you may encounter on a visit to Germany. It will help you ask the questions and, with practice, understand the answers. The extra vocabulary and phrases are particularly useful.