I don't think there are differences between the secondary accent and non-stress part when pronouncing..But in IPA,, there is a comma like symbol stands for secondary accents . Why cannot omit them。？What are the differences???
Native speakers often reduce vowel or schwa, and connect words when speaking, so difficult for non-native speakers to recognise exact word what they are talking. This makes confusing in listening and get ideas of speaker.
Hello, Yan Chu, you ask an excellent question. It is true that mixing up the secondary stress and the non-stressed stressed syllable is not as disastrous as mixing up the primary stress and the non stressed syllable, however the three stress system (primary, secondary, and non-stressed aka reduced) is crucial to mastering English pronunciation as well as listening comprehension. It's interesting to note that all non stressed syllables have the same vowel, the reduced vowel or schwa. This "schwa" is by far the most common sound in the entire English language, so mastering it will make your English sound much more native and will improve your listening skills astronomically. Tell me, is listening comprehension your biggest weakness?
You are right, Mit. That's why, if a non-native speaker practices "linking" as well as the "schwa," they will have a much easier time understanding and mastering spoken English.