Here are some specific examples of word pairs that sound the same or are very similar to each other, except for the fact that they have different syllable stress. Stress is what makes each word in the pair distinct from the other, and mixing up the stress on these words (or saying the words without a clear stress pattern) may cause confusion. Stressed syllables are in bold:

access | excess |
advantages | advantageous |
affect | effect |
comedy | committee |
decade | decayed |
desert | dessert |
eligible | illegible |
envelope | envelop |
moral | morale |
noble | Nobel [as in Nobel prize] |
rockets | Rockettes |
personal | personnel |
To be understood clearly, be sure to pronounce each word with the bolded syllables spoken slightly louder and for a slightly longer time than the surrounding syllables.
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