Dulcie C. answered 09/08/21
Speech Therapist of 25 years trained in Orton-Gillingham and SWI
Joanna B is absolutely correct. What we also notice is a shift in stress. When these words are used as nouns, the stress is on the first syllable. When used as a verb, the stress is on the second syllable. This can be helpful when spelling. When a syllable is not stressed, the vowel is reduced to a schwa. Schwas are hard to spell unless you know the family members. For example, in the first word "progress", the 'o' is a schwa when it's a verb like in the sentence, "How will they progress past the first level." The <o> is not clearly pronounced without stress on it. If a writer knows the same word can be pronounced differently as in the noun "progress" (His progress has increased.), then they can more clearly hear the short 'o' sound and more easily spell it.