It's really important to show students exactly what they can do with English. It's equally important to hold up examples of other learners, in order to highlight the future goal... which could take a long time to achieve, yet which is achievable.
But not all motivational methods work the same. The above examples would be for students who have picked up English as a hobby, or who have nebulous plans (e.g., "I want to speak to people from other countries.") More serious students would need to set goals, so as to measure progress on the road to their ultimate goal (e.g., "I want to improve my English so I can study in London.").
Here's a good article on setting goals with students:
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