感覺是不一樣的，相關的發音視頻見內，供你參考。

1. cup, hut, love.



English: How to Pronounce UH as in BUTTER [/ ] vowel
https://www.youtube.com/watch?v=sJupiMmsbx0



American Accent 60 Words with "uh"  [/ ] Vowel Sound - American English Pronunciation Lesson
https://www.youtube.com/watch?v=ausxODBl6m0

2. ago, sofa



English: How to Pronounce the Schwa(英語中非重讀音節的元音) [?] -- American Accent https://www.youtube.com/watch?v=rM9NxK74JSE