Is it possible to tell them that you want to be a toll collector? garbage collector? toilet cleaner? maid? dish washer? farmer? fisherman? gardener? drug dealer? porn star? or pimp? or porn director?
I'm pretty sure you'll get this expression.
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This doubt has been bothering me for quite some time: is it not ok to not have a ambition? Why does your own ambition have to do with other people's expectations?