adjective
BAD : Some former prisoners are now respectful citizens.
GOOD : Some former prisoners are now respectable citizens.
BAD : If you wish to make a good impression, you'll have to look a bit more respectful.
GOOD : If you wish to make a good impression, you'll have to look a bit more respectable.
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respectful = having or showing respect for someone, especially someone older than you or senior to you: 'The principal has warned him that unless he shows a more respectful attitude towards his teachers, he will have to leave.'
respectable = displaying socially acceptable standards in appearance or behaviour: 'Surprisingly, many of these young offenders come from respectable families.' 'Nobody is going to give you a job unless you make yourself look a bit more respectable.'