Thai vowels with very similar sounds, help!
I've been working on pronunciation thoroughly before I move on to anything else in Thai, however there are a few vowels that sound extremely similar to me and I can't find much info on how and where they are pronounced in the mouth.

These vowels are:
เออ/เออะ and เอิ both sound very similar to อื/อึ.

อื/อึ are pronounced at the top of the mouth with the lips spread wide open and mouth closed.

Then with regards to เออ/เออะ and เอิ I'm really not sure how are they are pronounced. It seems like the lips might be looser and the mouth isn't spread as wide? I am really not sure though.

Any help is extremely appreciated, thank you for reading!

Additionally, if someone could record these examples below and explain their mouth shape + where exactly the vowel is pronounced in the mouth, that would be extremely helpful.

1. เออ เออะ / อือ อึ

2. เกอ เกอะ / กือ กึ

3. เกิน / กืน กึน

Question

Thai vowels with very similar sounds, help!
I've been working on pronunciation thoroughly before I move on to anything else in Thai, however there are a few vowels that sound extremely similar to me and I can't find much info on how and where they are pronounced in the mouth.

These vowels are:
เออ/เออะ and เอิ both sound very similar to อื/อึ.

อื/อึ are pronounced at the top of the mouth with the lips spread wide open and mouth closed.

Then with regards to เออ/เออะ and เอิ I'm really not sure how are they are pronounced. It seems like the lips might be looser and the mouth isn't spread as wide? I am really not sure though.

Any help is extremely appreciated, thank you for reading!

Additionally, if someone could record these examples below and explain their mouth shape + where exactly the vowel is pronounced in the mouth, that would be extremely helpful.

1.    เออ เออะ / อือ อึ

2.    เกอ เกอะ / กือ กึ

3.    เกิน / กืน กึน

Answer

Please find my reply as below :-

1. เออ   is a long vowel and pronounced as '' er ''  English word with similar sound in Thai is as ''her '',
  /เออะ is short vowel and pronounced as '' er'' but you have to say quicker than the vowel '' เออ'' English word with similar sound in Thai is as '' the''.
 / อือ is a long vowel and pronounced as '' eu '' /
 อึ is short vowel and pronounced as '' eu'' but you have to say quicker than the vowel '' อือ''   
 Remark  EU = E+U spoken together as one diphthong

2. เกอ  Ger ( long sound) / เกอะ Ger ( short sound) / กือ Geu ( long sound) กึ  Geu ( short sound)

3. เกิน Gern  ( long sound) / กืน Geun ( long sound) / กึน Geun ( short sound)

Hope this helps

Answer

Thai vowels have long sounds and short sounds 
เออ อือ เกอ กือ long sounds
เออะ อึ เกอะ กึ short
And 3 questions เกิน กืน กิน is have final sounds