The Unconditional Guru

To understand this topic we have to see the structures of both by taking simple examples.

CH₃CONH₂ – Amide and CH₃CH₂NH₂ –Amine  

here as it is clear in the upper structures, on case of amides, the nitrogen atom is joined with oxygen. being more electron attracting , the oxygen decreases the electron density on nitrogen atom.

on the other hand being electron releasing in nature the CH₃CH₂ ethyl group increase the electron density on NH₂ thus making it more basic.