Compound Vowels
Learn compound vowels: ㅐ, ㅔ, ㅘ, ㅙ, ㅚ, ㅝ, ㅞ, ㅟ, ㅢ, ㅑ, ㅕ, ㅛ, ㅠ
Compound vowels are built by combining the basic vowels you learned in Lesson 1-1. ㅑ, ㅕ, ㅛ, ㅠ are simply ㅏ, ㅓ, ㅗ, ㅜ with an extra short stroke that adds a 'y' sound at the front — so ㅑ is 'ya', ㅕ is 'yeo', and so on. The wider compounds like ㅘ, ㅝ, ㅚ, ㅟ combine two simple vowels into a true diphthong.
The most confusing pair for beginners is ㅐ vs ㅔ. Historically these were two different sounds, but in modern Seoul Korean they have merged into a single sound roughly like English 'eh'. You will still see both spellings in different words (애 vs 에), but you do not need to worry about distinguishing them in pronunciation. Practice reading words that use the compounds you have already learned in syllable blocks — vowels become real as soon as you see them inside actual Korean words rather than in isolation.
Y-vowels: Adding a 'y' sound
Adding an extra stroke to basic vowels creates 'y-' versions: ㅏ→ㅑ (a→ya), ㅓ→ㅕ (eo→yeo), ㅗ→ㅛ (o→yo), ㅜ→ㅠ (u→yu). The pattern is simple: one extra stroke = add 'y'.
How It Works
Compound vowels are built by two different operations, and separating them makes the set far less intimidating. The first operation is adding a stroke: ㅏ→ㅑ, ㅓ→ㅕ, ㅗ→ㅛ, ㅜ→ㅠ. One extra short stroke always means the same thing — put a 'y' glide in front. There are no exceptions to this, so four of the thirteen are free once you know the four basic vowels they come from.
The second operation is genuine combination. ㅘ is ㅗ written together with ㅏ, and it is pronounced exactly that way: the lips start rounded for ㅗ and slide open into ㅏ. ㅝ is ㅜ plus ㅓ, ㅟ is ㅜ plus ㅣ, ㅙ is ㅗ plus ㅐ. The writing is not a code to memorise — it is a set of instructions for what your mouth should do in sequence.
ㅐ and ㅔ are the outliers. Historically ㅐ was ㅏ+ㅣ and ㅔ was ㅓ+ㅣ, which is why they are written that way, but in modern Seoul speech the two have merged into one sound. You still have to spell them correctly because they distinguish words, but you do not have to pronounce them differently. ㅢ is the last oddity: in careful speech it is ㅡ followed by ㅣ, but in ordinary speech it is frequently reduced to [이] or, in the possessive particle 의, to [에].
Where You'll Hear It
The y-vowels carry an enormous amount of everyday vocabulary. 여기 ('here') and 여자 ('woman') both open with ㅕ; 요 appears at the end of the polite verb ending that you will use in nearly every sentence for your first year of Korean. 유 shows up in 우유 ('milk'), which is on every convenience-store fridge in the country.
The true compounds cluster in high-frequency words too. 와 means 'and' when joining nouns and is also the sound of 왜 ('why') minus one stroke. 뭐 ('what') is built on ㅝ and is probably the single most common question word in casual speech. 위 means 'above' or 'top' and appears in directions constantly: 위층 ('upper floor'), and on lift buttons.
ㅐ and ㅔ are worth noticing in print even though they sound alike. 네 means 'yes' and is one of the first things you will say in Korea; 내 means 'my'. 개 is 'dog' and 게 is 'crab' — a pair Koreans themselves sometimes disambiguate out loud when ordering at a seafood restaurant. Seeing them written is how you learn which is which, because listening will not tell you.
Cultural & Language Note
The merger of ㅐ and ㅔ is a sound change that happened within living memory. Older Koreans, especially outside Seoul, may still distinguish them, and the spelling difference is preserved because it marks different words: 개 (dog) versus 게 (crab). Koreans themselves sometimes clarify over the phone by saying 'ㅏ 개' or 'ㅓ 게' — spelling out which vowel they mean, much the way English speakers say 'B for Bravo'.
Common Mistakes to Avoid
Learners often assume ㅚ and ㅙ and ㅞ must sound different because they are written differently. In modern standard Korean they are all pronounced essentially the same, roughly 'we'. Do not waste practice time trying to separate them — just memorise which spelling each word takes. The mistake that does matter is reading ㅢ as a single vowel; in 의사 (doctor) it is 'ui', but as a possessive particle 의 is pronounced 'e', and in non-initial position it is often just 'i'.
How to Practice This Lesson
Do not treat this as one list of thirteen. Split it in two: learn the four y-vowels in a single sitting, because they are pure arithmetic on vowels you already know, then spend your real effort on the true compounds.
For those, say the two source vowels slowly and then speed them up until they fuse — ㅗ...ㅏ...ㅗㅏ...ㅘ. Doing this out loud is the whole technique; the glide is a physical motion, not a fact to memorise. For ㅐ versus ㅔ, stop trying to hear a difference and switch to learning them as spellings attached to specific words. Write 개 and 게 side by side with a small drawing next to each, and let the picture carry the distinction.