What is the difference between these two vowels? Can someone explain the difference with combination vowels such as เอือะ and เอือ? I think they are short and long but when written they seem to look the same because the 'ะ' is dropped unless it appears at the end of a word. Could someone write words that use the vowels above to show how they are different? Thank you very much!

My first Thai Sentence! ดุณสบายคีไมดรับ? :)