Here's why:
* Stress: The stress in "listening" falls on the first syllable "lis".
* Unstressed Vowel: The vowel in the second syllable "ten" is unstressed. This means it has a reduced vowel sound, often represented by the schwa sound (ə).
* Spelling: The unstressed vowel in "listening" is spelled "i", but it is pronounced with the schwa sound.